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TIMING OF PREGNANCY RECOGNITION AS A
PREDICTOR OF PRENATAL INITIATION AND BIRTH
OUTCOMES

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ADEJOKE BOLANLE AYOOLA

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TIMING OF PREGNANCY RECOGNITION AS A PREDICTOR OF PRENATAL
CARE INITIATION AND BIRTH OUTCOMES

By

Adejoke Bolanle Ayoola

A DISSERTATION

Submitted to
Michigan State University
in partial fulﬁllment of the requirements
for the degree of

DOCTOR OF PHILOSOPHY
College of Nursing

2007

ABSTRACT

TIMING OF PREGNANCY RECOGNITION AS A PREDICTOR OF PRENATAL
CARE INITIATION AND BIRTH OUTCOMES

By

Adejoke Bolanle Ayoola

The time that a woman recognizes her pregnancy is crucial to the eventual birth
outcomes. The relationship between the time of pregnancy recognition and birth
outcomes is yet to be fully explored. In addition, a woman who does not recognize her
pregnancy early may not initiate prenatal care (PNC) early and may continue unhealthy
behaviors throughout the pregnancy. This study examined whether the time of pregnancy
recognition predicts the time of initiation of PNC, the number of prenatal visits and birth
outcomes such as prematurity, low birth weight, rates of admission in Neonatal Intensive
Care Unit (N ICU) and infant mortality. The study is a secondary data analysis of the
Pregnancy Risk Assessment and Monitoring System (PRAMS) multi-state data for
United States from 2000-2004. The PRAMS program entails cross-sectional surveys,
addressing maternal behaviors and experiences that occur before, during, and shortly
after pregnancy among US. women of childbearing age. The analysis involved weighting
of complex survey data using STATA9.2 software. Binary and multinomial logistic
regressions were used for the analyses. Of the 136,373 women in the study, 72.4%
recognized their pregnancy within 6 weeks. Ninety percent of the women had recognized
their pregnancy by 12 weeks and 80% had initiated PNC by 12 weeks. Early pregnancy
recognition is a strong predictor of early PNC initiation, and a moderate predictor of

reduced premature births, reduced LBW babies and NICU admissions. Promotion of

early pregnancy recognition by nurses may be effective in improving birth outcomes, if

they are part of routine reproductive health care services for women of childbearing age.

Copyright by
ADEJOKE BOLANLE AYOOLA

2007

To God through whom all blessing ﬂow!

ACKNOWLEDGEMENTS

Special thanks to Manfred Stommel, PhD, the chair of my Dissertation
Committee, Mary Nettleman, MD, MS, Audrey Gift, RN, PhD, Larry Hembroff, PhD,
Renee Canady, PhD, and Linda Spence, RN, PhD, for their encouragement, support and

guidance throughout my doctoral studies.

My appreciation also goes to the faculty and staff of Michigan State University
College of Nursing, Calvin College Department of Nursing and my colleagues for

providing very good environment for me to learn, and develop my potentials.

My thanks also go to my parents and other family members, in-laws, friends, and
church families including University Baptist Church for their assistance, encouragement
and great support during my doctoral studies. Special thanks to Dr Asopuru Okemgbo for

being a visionary and constant source of encouragement.

My great appreciation is expressed to my husband, Bernard T Ayoola, and
children, Ayooluwa, Adeoluwa, Ireoluwa and Ifeoluwa, for their love, encouragement,
understanding and numerous assistance and support to ensure that this program is

completed.

Funding sources for this project include Michigan State University Graduate
Fellowship; Blue Cross Blue Shield of Michigan Foundation; and American Nurses

Foundation and Midwest Nursing Research Society Research Award.

vi

TABLE OF CONTENTS

LIST OF TABLES ................................................................................. ix
LIST OF FIGURES ................................................................................. x
CHAPTER 1
Background and Scope .............................................................................. 1
CHAPTER 2
Review of Studies on Pregnancy Recognition and its Interrelationships with Prenatal
Care and Birth Outcomes ............................................................................ 8
Pregnancy and its Recognition ............................................................. 8
Time of Pregnancy Recognition and Prenatal Care .................................... 11
Time of Pregnancy Recognition and Birth Outcomes ................................. 17
Development of the Conceptual Model ................................................. 22
The social Cognitive Theory ..................................................... 22
Health Promotion Model ......................................................... 24
The Conceptual Model and the interrelationships between the Concepts .......... 27
Relationship between the Theories Guiding the Study and the Concepts in the
Model ........................................................................................ 31
Hypotheses .................................................................................. 34
CHAPTER 3
Methodology ......................................................................................... 35
Research Design ............................................................................ 35
Overview of PRAMS ...................................................................... 35
Sample and Setting ........................................................................ 36
PRAMS Data Collection Procedure ..................................................... 38
Protection of Human Subjects ............................................................ 39
Instruments .................................................................................. 40
Variables .................................................................................... 42
Data Analysis ............................................................................... 50
CHAPTER 4
Results ................................................................................................ 59
Data ‘Cleaning’: Missing or Misleading Data ......................................... 59
Recoding of Key Variables ............................................................... 61
Predictors of Missing Information ....................................................... 61
Population Description .................................................................... 66
Time of Pregnancy Recognition ......................................................... 66
Time lag between the Time of Pregnancy Recognition and the Time of PNC
Initiation ..................................................................................... 74
Hypothesis 1 ................................................................................ 75

vii

Hypothesis 2 ................................................................................. 78

Hypothesis 3 ................................................................................. 83
Hypothesis 4 ................................................................................. 87
Hypothesis 5 ............................................................................... 105
CHAPTER 5
Discussion ................................................................................. 107
Prevalence of Early Pregnancy Recognition and Early PNC
Initiation ........................................................................... 107
Consequences of Early Pregnancy Recognition ............................. 109

Time of Pregnancy Recognition as Predictor of Participation in PNC...109
Time of Pregnancy Recognition as Predictor of Early PNC Initiation... 1 1 1
Time of Pregnancy Recognition as Predictor of the Number of Prenatal

Visits .............................................................................. 117
Pregnancy Recognition and Birth Outcomes ................................. 119
Time lag and Birth Outcomes .................................................. 121
Limitations of the Study ........................................................ 124
Nursing Implications ............................................................ 126
Future Nursing Research ............................................... 126
Nursing Practice ......................................................... 129
Policy and Public Health Implications ........................................ 131
Conclusion .......... , .............................................................. I33
APPENDICES
Appendix A- Relationship between Time lag, Pregnancy Recognition, and
Time of Prenatal Care Initiation ........................................................ 137
Appendix B- State Distribution in the Analysis Sample ............................ 138
Appendix C- PRAMS Questionnaire .................................................. 139
Appendix D- Deﬁnition of Terms ...................................................................... 155
Appendix E- IRB Documents ............................................................................. 157
REFERENCES .................................................................................................... 159

viii

LIST OF TABLES

Table 1. Operational Deﬁnitions of the Main Variables in the Study .................. 44-45
Table 2. Operational Deﬁnitions of the Possible Confounders or

Control Variables ...................................................................... 46-49
Table 3. PRAMS Response Categories and Coding for the Analysis .................... 52-57
Table 4. Comparison of the Analysis Sample and the Missing Sample .................. 63-65
Table 5. Other Characteristics of the Analysis Population of 5,509,817 estimated
postpartum women ............................................................................ 67-68
Table 6. Characteristics of Women who recognized their Pregnancies Early and those

who recognized their Pregnancies Late ............................................ 70-73
Table 7. Logistic Regression Model Predicting Participation in PNC ................... 76-77
Table 8. Logistic Regression Model Predicting Early Initiation of PNC ................ 80-81
Table 9. Multinomial Logistic Regression Model Predicting Frequency of PNC Visits

(reference category: 11-15 PNC Visits) ........................................... 84-86
Table 10. Descriptive Analysis of the Birth Outcomes of the Analysis Population of

5,509,817 estimated postpartum women ............................................. 89

Table 11. Some Characteristics of Women Based on Birth Outcomes .................. 91-98

Table 12. Logistic Regression Model Predicting the Four Main Outcomes (Prematurity,
LBW, Admission into NICU and Infant Mortality ............................ 100-103

Table 13. Predictive Effect of Early Pregnancy Recognition on the Intermediate and
Ultimate Outcomes in the Study ...................................................... 113

ix

LIST OF FIGURES

Figure 1. Conceptual Model explaining the Relationship between Pregnancy
Recognition, Prenatal Care and Birth Outcomes ................................... 28

Figure 2. Relationship between time lag, pregnancy recognition and time of prenatal care
initiation ................................................................................. 137

CHAPTER 1
Background and Scope

The United States has the highest infant mortality rate among the industrialized
countries (Hamilton, Minino, Martin, Kochanek, Strobino, & Guyer, 2007). After
declining fairly steadily for about four decades, the infant mortality rate unexpectedly
increased from a low of 6.8 per 1000 live births in 2001 to 7.0 per 1000 births in 2002
and has remained higher since (US. Census Bureau, 2007). Thus, it remains a high
priority to investigate factors which contribute to infant mortality. Among several factors,
the mothers’ preconceptual and prenatal behaviors have been associated with infant
mortality and other adverse birth outcomes. For example, delayed and/or lack of prenatal
care (PNC) have been associated with increased risk of preterm birth (birth before 37
weeks) and congenital malformations (Carmichael, Shaw, & Nelson, 2002; Krueger &
Scholl, 2000; Vintzileos, Ananth, Smulian, Scorza, & Knuppel, 2002). Smoking and
alcohol consumption during pregnancy greatly affect birth outcomes such as gestational
age at birth, and birth weight (Hoyert, Mathews, Menacker, Strobino, & Guyer, 2006;
Mariscal, Palma, Llorca, Perez-Iglesias, Pardo-Crespo, & Delgado-Rodriguez, 2005).

However, women can only initiate PNC or adopt a health promoting behavior
when they recognize their pregnancy. When women recognize their pregnancy, they tend
to stop or reduce unhealthy behaviors (Kost, Landry, & Darroch, 1998; Ockene, Ma,
Zapka, Pbert, Goins, & Stoddard, 2002; Pirie, Lando, Curry, McBride, & Grothaus,
2000). Thus, the time of pregnancy recognition may be crucial to initiation of PNC, fetal
development, and possibly the eventual birth outcomes. The early pregnancy period

within the ﬁrst 6 to 8 weeks is very important for normal development and growth of the

fetus, because this is the stage when major fetal organs are formed (Hobbins, 2003).
Conversely, a delayed recognition of pregnancy can increase the risk of fetal exposure to
behavioral, medical, nutritional and drug-related conditions that interfere with normal cell
growth and development as well as favorable birth outcomes ( Alvik, Heyerdahl,
Haldorsen, & Lindemann, 2006; Carmichael et al., 2002; Center for Disease Control and
Prevention (CDC), 2006; Hellerstedt et al., 1998; Hobbins, 2003; Kost etal., 1998).

The ﬁnancial and emotional costs of poor birth outcomes to families and society
in the US. are enormous (Institute of Medicine (IOM), 2006). Preterm birth and low
birth weight (LBW) (birth weight below 2500grams) have been identiﬁed as the main
contributors to the consistently high infant mortality and morbidity rates as well as costs
of care in the United States (Goldenberg & Culhane, 2007). In 2005, preterm births
accounted for 12.7% of all births in the U.S., which is an increase of over 29% in the last
two decades from 9.4% in 1981 (Hamilton et al., 2007; Hoyert et al., 2006; Martin,
Hamilton, Sutton, Ventura, Menacker, & Kirrneyer, 2006). The national average for
LBW is 8.2%, making it the highest level reported since 1968, and almost double the 5%
goal for Healthy People 2010 (United States Department of Health and Human Services
(USDHHS), 2000). Babies born prematurely at 30 to 34 weeks have been reported to
have substantial morbidity (Marret et al., 2007). Nearly one-half of all neurological birth
defects (e.g., cerebral palsy) have been associated with preterm births (Martin, Hamilton,
Sutton, Ventura, Menacker, Munson, 2005). In addition, preterm and LBW babies have
often been reported to require admission to neonatal intensive care unit (N ICU) as well as
being at high risk for infant mortality (Hamilton et al., 2007; Marret et al., 2007).

Within the last two decades, PNC has been one of the several interventions

designed to improve maternal and child health in the US (Chang, O’Brien, Nathanson,
Mancini, & Witter, 2003; Moos, 2006; Taylor, Alexander, & Hepworth, 2005; Vintzileos
et al., 2002). As part of the efforts to improve birth outcomes in the Unites States,
Healthy People 2010 sets the goal that at least 90% of women in United States should
initiate PNC within the ﬁrst trimester of their pregnancies (U SDHHS, 2000). Currently
84% of pregnant women initiate PNC within the first trimester, which is still below the
national goal for Healthy People 2010 (Martin et al., 2005). Although the beneﬁcial
effects of PNC have been reported in some studies (Chang et al., 2003; Moos, 2006;
Taylor et al., 2005; Vintzileos et al., 2002), trends in pregnancy and birth outcomes in the
US. reveal the need to explore additional means to develop effective strategies.

The time of pregnancy recognition, appears to be an important factor that needs to
be explored in order to develop new strategies to improve birth outcomes. The Healthy
People 2010 goal of having a positive impact on birth outcomes through early initiation
of PNC within the ﬁrst trimester presupposes that women recognize their pregnancies
sufﬁciently early, since initiating PNC cannot commence until a woman recognizes that
she is pregnant. According to Hobbins (2003, p.517), “for most women the ﬁrst PNC
visit, with its risk assessment, counseling, laboratory studies, and recommendations for
intervention, takes place after the die has been cast.”

The time a woman recognizes her pregnancy might also inﬂuence the number of
PNC visits she makes. A delay in pregnancy recognition most likely leads to a higher
gestational age at ﬁrst PNC visit and a possible reduction in number of PNC visits made
during pregnancy (Kost et al., 1998; Morroni & Moodley, 2006; Petrou, Kupek, Vause &

Maresh, 2001). Early pregnancy recognition (conﬁrmed pregnancy within 6 weeks of

gestation) enables a woman to initiate PNC at the early stage of pregnancy when
organogenesis is still taking place. She is also able, at this stage, to think about
preconceptual and prenatal behaviors that can negatively impact the grth and
development of the fetus. However, when pregnancy recognition is delayed— especially
for hi gh-risk pregnant women such as primigravidas (women with their ﬁrst pregnancy),
adolescents, women with risky preconception behaviors such smoking and drinking or
those with pre-existing medical conditions such as diabetes — the risk of adverse
outcomes is likely to increase (Floyd, Decouﬂe, & Hungerford, 1999; Hoyert et al., 2006;
Moos, 2006).

The cessation or reduction of risky behaviors has been associated with improved
birth outcomes, such as reduction in LBW and premature babies (Alvik et al., 2006;
Carmichael et al., 2002; Hellerstedt et al., 1998). It has been observed that women tend
to quit totally or reduce smoking and drinking, when they realize that they are pregnant
(Kost et al., 1998; Ockene et al., 2002; Pirie et al., 2000). Pre-existing medical conditions
- such as asthma, cardiac disease, hypertension, thyroid disorder and diabetes - in women
of childbearing age greatly affect pregnancy and birth outcomes (CDC 2006; Kooistra,
Crawford, Van Baar, Brouwers & Pop, 2006). If pregnancy is not recognized early, pre-
existing medical conditions may not be promptly and adequately managed or controlled
very early in pregnancy, resulting in an exacerbation of adverse pregnancy or poor birth
outcomes.

Early recognition of pregnancy can facilitate early screening and management of
various conditions that can negatively affect birth outcomes. Exposure to teratogenic

medications and medical diagnostic procedures and managements (e. g., X-rays) during

the stage of cell differentiation in early pregnancy, can negatively impact fetal
development and growth. Such toxic exposure in the ﬁrst trimester is predictive of
preterm labor in later pregnancy. CDC (2006) reported that some women at risk of
pregnancy take medications that are teratogenic. Consumption of these teratogenic
medications early in pregnancy can affect fetal growth leading to preterm birth and
babies with LBW (CDC, 2006).

Existing studies have not examined the relationship between the time of
pregnancy recognition and birth outcomes such as prematurity, LBW, admission to NICU
and infant mortality (death of an infant within one year of birth). Predictors of initiation
of PNC such as the socio-demographics, parity, psychosocial and health system-related
factors have been extensively studied -- except for the effect of the time of pregnancy
recognition. There is a dearth of population-based representative information about the
impact of time of pregnancy recognition on women’s time of PNC initiation and number
of PNC visits. In order to develop evidence-based interventions, there is also a need to
know, which women are particularly vulnerable to late pregnancy recognition and which
women do not initiate PNC despite having recognized that they are pregnant. In addition,
there is a need to know whether the time of pregnancy recognition predicts poor birth
outcomes such as prematurity, LBW, admission to a NICU and infant mortality.

This study therefore examines the relationship between time of pregnancy
recognition, time of PNC initiation, and number of PNC visits using the data from a large
population-based survey by the Pregnancy Risk Assessment Monitoring Surveillance
(PRAMS) in the US. The focus of this study is two-fold:

1) To determine the extent to which early recognition of a pregnancy (conﬁrmed

pregnancy within 6 weeks of conception) predicts early initiation of PNC (start

PNC within 12 weeks of conception) and the number of PNC visits.

2) To explore how early pregnancy recognition affects birth outcomes such as
gestational age at birth, birth weight, rates of admission to NICUs and infant
mortality.

The focus of this study is not on the examination of the small group of women
who had no PNC. Although some women might not have PNC whether they recognize
their pregnancy early or late, the percentage of women who do not receive PNC at all is
likely to be negligible when compared with those who had PNC. The PRAMS 2002
surveillance report stated that more than 97% of women in the United States, who had a
live birth in 2002, received PNC (Williams, Morrow, Shulman, Stephens, D’Angelo, &
Fowler, 2006). This means that less than 3% of pregnant women had no PNC. The
national vital statistics also revealed that, for the US in 2003, about 3.5% of pregnant
women began PNC in the last trimester or had no PNC (Martin et al., 2005). This
reported percentage refers both to women who had late PNC (started in the last trimester)
and those who had no PNC at all, which means that the percentage of women with no
PNC at all is even less than the reported 3.5% (Martin et al., 2005).

A more speciﬁc report from State of Michigan PRAMS revealed that the .
percentage of women with no PNC was 0.7% in 2002 and 1.1% in 2003 (Michigan
Department of Community Health (MDCH), 2005, 2006). Therefore, the focus of this
study is primarily on the timing of the ﬁrst PNC visit and the number of PNC visits

among the vast majority of women who have at least one PNC visit during their

pregnancy.

This study seeks to add to the understanding of time of pregnancy recognition as a
relevant construct in nursing, and a potentially modiﬁable behavior. Since time of
pregnancy recognition is likely to be an important predictor of PNC initiation, number of
prenatal visits, and eventual birth outcomes (prematurity; LBW; admission to NICU and
infant mortality), the knowledge of these relationships will guide the design of
evidenced-based nursing interventions for promoting maternal and child health during
pregnancy.

Nurses are in a variety of health care settings that provide necessary information
and guidance to encourage women to adopt health-promoting behaviors to attain an
optimal level of wellness. Activities within the domain of nursing health promotion may
include: 1) teaching and counseling around early recognition of pregnancy in terms of
knowing signs and symptoms of pregnancy as well as home pregnancy testing; 2)
encouraging early PNC initiation; 3) Assisting women to modify behaviors such as
smoking or drinking alcohol during pregnancy. Thus, nurses can assist in guiding women
through the reproductive life span as they move through the preconceptual and
interconceptional periods (Misra, Guyer, and Allston, 2003). Adoption of these health-
promoting behaviors can ultimately contribute to the reduction of pregnancy-related

infant morbidity and mortality.

CHAPTER 2
Review of Studies on Pregnancy Recognition and its Interrelationships with Prenatal
Care and Birth Outcomes
Pregnancy and its Recognition

Pregnancy is a physiological condition during which a fertilized ovum is nurtured,
develops to maturity, and ends in the birth of a child (Hobbins, 2003). The ﬁrst few
weeks of fetal development are critical to the eventual health of the child. The critical
phase of cell organization, differentiation and organ development takes place 17 to 56
days after conception. The heart starts to beat and major organs are formed by the 8th
week of gestation. This early period is of greatest environmental sensitivity and risk for
the developing embryo (Hobbins, 2003). Alteration or interference with the process of
organogenesis during this early stage of pregnancy can result in various congenital
malformations. The pregnancy period is very important, since it involves the health of the
mother and the fetus and requires adequate prenatal management to promote positive
pregnancy/birth outcomes. However, for care to be initiated, pregnancy must be
recognized; the mother must acknowledge the existence of the fertilized ovum and
growing fetus.

Maternal pregnancy recognition has been conceptualized in terms of three main
perspectives in the literature. First, pregnancy recognition has been described as a
physiological process whereby the mother responds to the presence of a conceptus within
her reproductive tract (Roberts, Xie, & Mathialagan, 1996; Spencer & Bazer, 2004).
Maternal recognition is triggered by the level of hormones released by the conceptus and

subsequently identiﬁed by the mother’s body (Beehr, Stone, & Foote, 1995). Most of the

studies in this line of research have considered maternal pregnancy recognition among
animals (e.g., Spencer & Bazer, 2004), but a few have focused on humans (e.g., Beehr et
al., 1995) or both humans and animals (Roberts et al., 1996). Spencer & Bazer (2004)
report that, for mothers to recognize their pregnancies (i.e., the mother’s body identiﬁes
the existence of a conceptus from the signals sent to the body from the hormones),
embryonic implantation must have occurred.

The second type of research describes maternal pregnancy recognition as a
“complex and sometimes protracted process that includes assessing pregnancy risk;
perceiving and correctly interpreting pregnancy signs and symptoms; seeking
conﬁrmation, accepting (or denying) the pregnancy; disclosure to others and deciding
actively or by default to continue with the pregnancy” (Peacock et al., 2001 p.110). This
second line of research is different from the physiological perspective in that it focuses
more on the psychological and psychosocial processes of acknowledging and accepting
the existence of a conceptus.

The presence of pregnancy hormones does not immediately translate into signs
and symptoms of pregnancy. The woman’s body may have physiologically identiﬁed the
possible existence of a conceptus, but the woman may not know or be sure that
pregnancy has occurred. There is, therefore, a possible lag between conception and the
time that women actually recognize, or are sure of their pregnancy. While the process of
pregnancy recognition is a complex psychosocial process, it encompasses both the
“knowing” of the existence, and the conscious acceptance of the pregnancy.

The third type of research concerning maternal pregnancy recognition focuses on

when women suspect their pregnancy (Edwards & Werler, 2006) or conﬁrm the actual

existence of a developing fetus (Kost et al., 1998). Kost et a1. stated that pregnancy
recognition occurs, if the woman knows she has conceived. “Knowing,” as
operationalized in Kost’s study, is based on a home pregnancy test kit; a strong suspicion
of pregnancy; or a formal ofﬁce or clinic test to conﬁrm pregnancy. This conﬁrmatory
perspective conceptualizes recognition as a one-time experience of suspecting or
conﬁrming pregnancy. Pregnancy conﬁrmation could be based on signs and symptoms of
the pregnancy or the procedure of having a pregnancy test to conﬁrm the existence of a
fetus, either at home or in a hospital or clinic. Many studies on the impact of pregnancy
recognition on women’s preconceptual behaviors and PNC initiation have used a
woman’s self-reported date of when she suspected or knew she was pregnant (Edwards &
Werler, 2006; Kost et al., 1998), or urine pregnancy testing (Morroni & Moodley, 2006),
as the time of pregnancy recognition. Sometimes, when a woman’s body recognizes the
existence of a conceptus due to hormonal changes, the pregnant woman may suspect, but
may not yet be fully conscious of the actual existence of the pregnancy, until a pregnancy
test has been conducted to conﬁrm the existence of the fetus.

The current study does not examine the process of pregnancy recognition per se;'
rather, the objective here is to examine the consequences of the one-time experience of a
mother, as she conﬁrms and acknowledges that a developing conceptus exists in her
womb. The study is designed to examine the subsequent behavioral changes that a
woman may engage in after recognizing (conﬁrming) that she is pregnant; such as the
decision to initiate PNC. This study examines both the time of initiation of PNC and the
number of PNC visits. These two variables are considered to be an important part of

adequate PNC (Kim, Mandell, Crandall, Kuskowski, Dieperink & Buchberger, 2006;

10

Mikhail, 1999), but the focus of this study is not on the adequacy of the content of PNC.
From the point cf view of pregnancy recognition, deﬁned as either suspecting or
conﬁrming the pregnancy, the time of initiation of PNC and the number of PNC visits are
considered intermediate outcomes in this study.

For a woman to recognize her pregnancy or to be sure she is pregnant, the
physiological recognition of the conceptus most likely would have taken place. Although
there have been a few cases of women who believed they were pregnant even though
they were not, there is a general consensus that conscious recognition of a pregnancy
generally occurs after implantation (Beehr et al., 1995; Anonymous, 2003). Implantation
of the conceptus occurs at varied times for pregnant women. It usually begins 6 — 7 days
after ovulation (Beehr et al., 1995), but pregnancy recognition usually does not occur
until the ﬁrst missed period, occurring after the ﬁrst day or even as late as a week after a
missed period for about 10% and 3% of pregnancies respectively (Anonymous, 2003).
This shows that the earliest time for a pregnancy to be conﬁrmed could be around 5
weeks in about 3% of pregnancies.

In summary, pregnancy recognition has been described from a physiological
perspective and, psychosocially, based on subjective acceptance and conﬁrmation. Since
there are some pregnancies that might not be recognized until a week after missed period
(i.e., 5 weeks of gestation); this study deﬁnes “early pregnancy recognition” as
recognition occurring by the sixth week of pregnancy/ gestation. Gestational age is
usually calculated from the ﬁrst day of the last menstrual period.

Time of Pregnancy Recognition and Prenatal Care

In the last two decades, very few studies have looked at the association between

11

pregnancy recognition and time of initiation of PNC. The study conducted by Kost et al.
(1998) analyzed ﬁndings from two national surveys that were conducted in 1988- the
National Maternal and Infant Health Survey (NMIHS) and the National Survey of Family
Growth (N SF G). The Kost et al. study is presently the only population-based study that
examined the predictive effect of pregnancy recognition on PNC use in the United States,
and was conducted within the context of pregnancy intention. . Kost et al. found a weak
association between maternal age and the time of pregnancy recognition. The relationship
is not statistically signiﬁcant and it is curvilinear. Initially the odds of recognition rise
with age and the highest is at 35 years, after which the odds of early recognition tend to
decline (Kost et al. 1998).

Kost et al. (1998) compared time of pregnancy recognition for women with
intended and unintended pregnancy. Kost et al. concluded that, in general, early
recognition of a pregnancy is a strong predictor of early PNC, and that women with
unintended pregnancies recognize their pregnancies later than women with intended
pregnancies. The study also found that, irrespective of the intention status of the
pregnancy, women do change their behaviors and adopt a healthier lifestyle when a
pregnancy is recognized.

In the same study by Kost et al. (1998), the analysis of the 1988 National Survey
of Family Growth (N SF G) revealed that about 56% of US. women of reproductive age
recognized their pregnancy within the ﬁrst 6 weeks of conception. While 67.7% of the
women in the National Maternal and Infant Health Survey (NMIHS) recognized their
pregnancy early (within 6 weeks of conception), a smaller percentage of women (60.1%)

actually initiated care within 8 weeks. This shows additional variation in the time of

12

pregnancy recognition and the time of initiation of PNC. However, Kost’s study does not
provide an explanation for the variation in this time lag. In addition, the study used data
that were collected almost two decades ago. Thus, it is time to examine the relationship
between time of pregnancy recognition and time of PNC initiation again.

Recent related studies have been conducted by Morroni & Moodley (2006),
Blackwell (2002) and Peacock et a1. (2001). Morroni & Moodley (2006) conducted their
study in South Aﬁica and reported that, when women recognized their pregnancies
earlier through access to home pregnancy testing, there was a decrease of 3.6 weeks in
the gestational age at ﬁrst PNC visit, independent of other factors. Blackwell (2002) in
her qualitative study on the relationship between pregnancy recognition and initiation of
PNC, described women’s PNC experience in the public and private arena. Using face-to-
face in-depth interviews to explore women’s PNC experiences, she concluded that
pregnancy realization was a major impetus for women to initiate PNC (Blackwell, 2002).
Although Peacock et al. (2001) (n = 87) focused only on women with their ﬁrst birth, it is
the only current study that discussed the process of pregnancy recognition. Peacock et al.
concluded that the process of pregnancy recognition is complex, and when protracted,
can potentially result in delayed initiation of both PNC and healthful pregnancy
behaviors. Both studies, by Blackwell and Peacock et al., are qualitative studies that used
small sample sizes.

When delay in initiation of PNC after pregnancy recognition occurs, it is due to a
host of other factors that have been well-documented in the literature (Bennett, Switzer,
Aguirre, Evans, & Barg. 2006; Bloom, Bednarzyk, Devitt, Renault, Teaman, & Van

Loock, 2004; Egerter, Braveman, & Marchi, 2002; Erbaydar, 2003; Gavin, Adams,

13

Hartrnann, Benedict & Chireau, 2004; Hulsey, 2001; Moore, Ketner, Walsh &Wagoner,
2004; Remez, 2003; Rittenhouse et al., 2003; Rosenberg, Handler, Rankin, Zimbeck, &
Adams, 2006). Women’s time of initiation of PNC has been associated with structural
and process factors within the health care system, such as access, patient-provider style of
communication, and location of health care clinic. The determinants outside the health
care system include personal and partner-related factors, some of which are signiﬁcant
variables that may be confounders with respect to the time lag between pregnancy
recognition and PNC initiation.

Personal factors reported to inﬂuence women’s PNC initiation include women’s
ages, parities, levels of education, and socio-economic statuses (Gerstein, 2000; Kost et
al., 1998; Yu, Alexander, Schwalberg & Kogan, 2001). The major reason given as a
barrier to early PNC in an earlier PRAMS study is “I didn’t know I was pregnant” (CDC,
2000). Peacock et a1. (2001) study on the process of pregnancy recognition focused on
only primiparas (pregnant women who have had only one birth), which suggests that the
number of previous live births could be a relevant factor in the time of pregnancy
recognition. Women who are pregnant for the ﬁrst time (primigravidas) are at higher risk
for not recognizing their pregnancies early (Y u et al., 2001). Kost et al. (1998) also
reported a weak association between parity and time of pregnancy recognition. Kost’s
study revealed that, on average, multiparous women (those who have had two or more
births) have greater odds of recognizing their pregnancy early than primiparous women
(those who have had only one prior birth). However, among the multiparous women, it
was only women with one previous live birth (adjusted Odds ratio = 1.22), and those with

three or more live births (adjusted Odds ratio = 1.27) that were signiﬁcantly more likely

14

to recognize pregnancies in the ﬁrst six weeks than women in their ﬁrst pregnancy (Kost
et al. 1998).

In terms of PNC, maternal age and parity (number of prior births) have been
reported to have great inﬂuence on time of PNC initiation. Women younger than 18 years
have been observed to be at increased risk for delayed or late care (initiating care after the
ﬁrst trimester) especially among the minority groups (e.g., African American, and Asian
American) in United states (Gerstein, 2000; Yu et al., 2001). Increasing maternal parity
has also been associated with risk of delayed PNC (Goldani, Barbieri, Silva, & Bettiol,
2004)

Women with low educational attainment and socio-economic status have also
been identiﬁed for an increased risk of initiatingPNC after the ﬁrst trimester (Kost et al.,
1998; Yu etal., 2001). Conversely, Kost et al. (1998) reported that women with some
college education and those with annual income of at least twice the federal poverty level
(FPL) were most likely to recognize their pregnancies early (Kost et al., 1998). Gerstein
(2000) also reported that, as a woman’s level of education increases, there is reduced risk
of late PNC initiation.

Additional factors that have been reported in the literature to inﬂuence the time of
initiation of PNC are: race/ethnicity, prior birth outcomes, women’s perceptions that PNC
is not important, fear that others ﬁnd out about their pregnancy, and unintendedness of a
pregnancy (Bennett etal., 2006; Daniels, Noe, & Mayberry, 2006; Hulsey, 2001;
Rosenberg et al., 2006; Rittenhouse et al., 2003).

Partner-related factors have been associated with early pregnancy recognition and

earlier PNC initiation (Kost et al., 1998; Yu et al., 2001). According to Martin,

15

McNamara, Milot, Halle & Hair (2007), women whose partners were involved in their
pregnancies by discussing the pregnancy, feeling the baby’s movement, going for
ultrasound, and childbirth or Lamaze classes together were 1.5 times more likely to
receive PNC in the ﬁrst trimester. Among Hispanic women, pregnancies that were
unintended by the mother, but were intended by the father, had a lower likelihood of
delayed care, when compared with pregnancies unintended by both parents (Sangi-
Haghpeykar, Mehta, Posner, & Poindexter, 2005). This protective effect of a father’s
pregnancy intention on early PNC initiation was found to be stronger among married than
non—married couples (Sangi-Haghpeykar et al., 2005). According to Yu et al. (2001),
women who were unmarried were also signiﬁcantly more likely to begin PNC late.

Women with prior adverse outcomes, such as LBW and infant death in their ﬁrst
pregnancy, are also more likely to begin PNC in the ﬁrst trimester of their second
pregnancies than those who do not experience these events (Elam-Evans, Adams,
Delaney, Wilson, Rochat & Mccarthy, 1997). This ﬁnding suggests that many women do
attempt to learn from past experiences to improve the chances of a healthy delivery.

The time of PNC initiation has also been associated with the type of insurance
coverage. Rosenberg et al. (2006), using the PRAMS data set, observed an association
between prepregrrancy Medicaid coverage and early PNC initiation among low-income
women whose delivery was paid for by Medicaid. According to the authors, it was
unclear whether or not this association should be attributed to the insurance status itself.
One possible reason given for such a ﬁnding by the authors is that Medicaid eligibility
criteria are more generous for pregnant women than for other women, which means that

women with pre-pregnancy Medicaid coverage are even poorer than women covered only

16

after they became pregnant. However, when low-income women on Medicaid were
compared with women not receiving Medicaid, low-income women on Medicaid were
more likely to report late PNC (27-42%) than were women not receiving Medicaid (6-
24%) (Gerstein, 2000). This may indicate that some of the women who were not
receiving Medicaid had private insurance.

Very few studies have examined the relationship between the time of pregnancy
recognition and the subsequent numbers of prenatal visits. The nurrrbers of prenatal visits
have been examined in controlled trials, which tested their effects on outcomes, such as
LBW, perinatal mortality, maternal morbidity such as pre-eclampsia and postpartum
anemia, and patient satisfaction among low-risk women (Carolli et al., 2001; McDuf’ﬁe,
Beck, Bischoff, Cross, & Orleans, 1996; Villar et al., 2001). These studies reported that
reduced numbers of PNC visits do not appear to have a negative impact on pregnancy
and birth outcomes, when compared with average or higher number of PNC visits
(Carolli et al., 2001; McDufﬁe et al., 1996; Villar etal., 2001). Still, Petrou and
colleagues (2001) revealed that higher gestational age at the time of PNC initiation
signiﬁcantly reduced the number of prenatal visits. This is to be expected, since later
recognition of a pregnancy implies a higher gestational age at the time of the initial
presentation for PNC, thus reducing the total number of visits the pregnant woman can
make.

Time of Pregnancy Recognition and Birth outcomes

In the United States, 12.7% of all births are preterm (Hamilton et al., 2007).

Although the increasing trend towards premature births has also been attributed to

multiple births, most preterm deliveries are single births (Hoyert et al., 2006). Preterm

17

births cost society at least $26 billion a year, or $51,600 per infant born preterm (IOM,
2006). Preterm births, and the LBW associated with them, are the second and third
leading causes of infant death in United States (Hamilton et al., 2007). They are also
independently associated with some delays in motor and social development through
early childhood (Hedi ger, Over-peck, Ruan, & Troendle, 2002). Similarly, preterm births
have also been associated with various physiological complications, including
respiratory, gastrointestinal, immune system, central nervous system, hearing, and vision
problems; longer-term problems include cerebral palsy, mental retardation, visual and
hearing impairments, learning difﬁculties, and poor health and grth (Institute of
Medicine (IOM), 2006). The increasing rates of preterm births and LBW in the US.
together with their physiological, emotional and economic challenges, make these two
conditions a growing public health problem that need to be adequately addressed.

Preterm and LBW babies are exposed to various perinatal complications as well
as later growth and developmental problems. Nearly one-half of neurological birth
defects (e.g., cerebral palsy) have been associated with preterm births (Martin et al.,
2005). The rate of postnatal complications associated with preterm births and LBW
increases the risk of admission into NICU. Preterm babies have been reported to be at
increased risk of admission into NICU and infant mortality (Hamilton et al., 2007).
Neonatal death has been reported among babies with moderately LBW (1500-2499
grams). The risk of early death for infants born with moderately LBW (1500-2499 grams)
in 2004 is 6 times greater than that of heavier babies (Hoyert et al., 2006).

The time of pregnancy recognition is an important concept, because it is likely

that pregiancy recognition will affect birth outcomes in various ways. First, there is a

18

consensus in the literature that pregnancy recognition is a strong factor for change in
mothers’ prenatal behavior (Kost et al., 1998; Morroni & Moodley, 2006; Ockene et al.,
2002; Pirie et al., 2000). If mothers do not recognize their pregnancies early, they might
not be able to change those behaviors that can negatively affect the growth and
development of the fetus.

Haas et al. (2005) found that adequacy of PNC, medical conditions and smoking
during pregnancy accounted for a substantial percentage (47.1%) of the risk of preterm
delivery. When PNC is not initiated early enough, medical conditions that can complicate
pregnancies will not be promptly diagnosed. Late diagnosis or inadequate management of
medical conditions such as diabetes, gestational diabetes, and pre-eclampsia
(hypertension in pregnancy), can result in poor outcomes such as prematurity and LBW
with subsequent increase in cost (IOM, 2006).

Mariscal et al. (2005) also reported that alcohol consumption of 12g/day or
greater increases the risk of LBW. Although part of Mariscal’s et al. (2005) ﬁndings was
that moderate alcohol consumption of less than 6g/day decreased the risk of LBW, this
ﬁnding is inconsistent with earlier studies (Olson, Streissguth, Sampson, Barr, Bookstein,
& Thicde, 1997; Sood et al., 2001). Handmaker, Rayburn, Meng, Bell, Rayburn and
Rappaport (2006) also reported in their study that, when women stop drinking early
during pregnancy, they tend to have children as healthy as those of other women who did
not drink.

Socio—demographic characteristics, such as age, race/ethnicity, and level of
education, have been associated with increased risks for preterm births, LBW, admission

to NICU and early infant death (Haas et al., 2005; Chang et al., 2003). For example,

19

maternal race is a factor that has been associated with preterm birth. Black women have
been identiﬁed to be at higher risk of having preterm births and LBW infants (Alexander,
Kogan, Bader, Carlo, Allen, & Mor, 2003; Vintzileos et al., 2002). In a prospective
cohort study of 1,619 pregnant women, who had single births, Haas et al. (2005) reported
that sociodemographic factors such as age, race, ethnicity, place of birth, level of
education and parity explained 13% of the risk of preterm delivery.

Extremes of maternal age have also been associated with an increased risk of
LBW deliveries. Mothers who are either very young (15 years and below) or rather old
for a pregnancy (above 45 years) have been observed to be at higher risk of having very
LBW babies compared to mothers that are within the 25 to 34 years age bracket (Martin
et al., 2005). A lO-year retrospective chart review of 1120 pregnant black adolescents, 17
years or younger, revealed a higher incidence of LBW infants, preterm deliveries and
fetal death than the normative data for the US. (Chang et al., 2003). Generally,
adolescents have a higher rate of premature births and LBW than older women (Gilbert,
Jandial, Field, Bigelow, & Danielsen, 2004).

Risk factors related to behaviors, both before and during a pregnancy, remain
potent predictors of birth outcomes. As mentioned earlier, Haas et al. (2005) showed that
prepregnancy body mass index (BMI) and smoking could explain 39.8% of the risk of
preterm delivery. A low prepregnancy BMI and inadequate weight gain during pregnancy
were also strong predictors of preterm births and LBW among pregnant black adolescents
(Chang et al., 2003). Birth data for the US in 2003 reveal that, as maternal weight
increases during pregnancy among women of initially moderate weight, the baby's birth

weight also increases (Martin et al., 2005). When the BMI effect was considered, based

20

on stratiﬁcation according to parity among 187,290 women in Scotland, women with no
prior birth (nulliparous) and a BMI of 35 or above had an increased risk of preterm birth,
infant mortality and delivery of extremely LBW infant (Smith, Shah, Pell, Crossley &
Dobbie, 2007).

The steady rise in maternal BMI has also been associated with an increasing trend
in adverse birth outcomes, such as admission into a neonatal unit, and infant mortality
(Cedergreen, 2004; Raatikainen, Hesikanen, & Heinonen, 2006). In a prospective
population-based cohort study, babies born to morbidly obese (BMI greater than 40)
women had an increased risk of early neonatal death when compared with babies born to
normal-weight mothers (Odds ratio (OR) - 3.41; 95% Conﬁdence Interval (CI) of 2.07,
5.63). Raatikainen et al. (2006) reported that the risk of fetal and perinatal death was high
among overweight (prepregnancy BMI = 26 to 29) and obese women (BMI _>_ 30) (OR =
1.54 to 2.19) and (OR = 1.54 to 2.35) respectively compared to women with normal BMI.
Since low prepregnancy BMI and inadequate weight gain during pregnancy has been
associated with the incidence of adverse birth outcomes such as prematurity (Chang et
al., 2003), it can be said that the relationship between BMI and adverse birth outcomes is
U-shaped. With higher rates at both extremes, of prepregnancy BMI and weight gain
during pregnancy.

Tam, Clark and Darcy (2006) reported an association between the amount of
maternal weight gain during pregnancy and the likelihood of the infant’s admission to a
NICU in a retrospective cohort study of 2,661 full-term singleton pregnancies. After
adjusting for age, method of delivery, parity and prepregnancy weight, the study

concluded that there was a signiﬁcant association between level of weight gain and NICU

21

admission. The lowest rate of NICU admission was in the range of weight gain from 30
to 35 pounds (2.6% of NICU admission rate) and 22 to 29 pounds (3.3% admission rate).
The study concluded that too much or too little weight gain could be a risk factor for
NICU admission.

The direct association between time of pregnancy recognition and birth outcomes
has not yet been explored in the literature. However, the various factors that affect birth
outcomes, such as adequacy of PNC (in terms of timely initiation and total number of
visits), has been signiﬁcantly associated with birth outcomes (Carmichael et al., 2002;
Mikhail, 1999). It is therefore relevant to examine the relationship between the time of
pregnancy recognition and adverse birth outcomes such as premature birth, LBW,
admission to NICUs and incidence of early infant death.

Development of the Conceptual Model

The goal of this study is to examine if and how the time of pregnancy recognition
affects women’s prenatal behaviors such as the time of PNC initiation and the likelihood
of various adverse birth outcomes. Therefore, it is appropriate to view such behaviors and
behavioral outcomes in the context of theories that consider factors that explain how
human behavior is inﬂuenced and can be changed. For this purpose, the Social Cognitive
Theory (SCT) (Bandura, 1977, 1986) and the Health Promotion Model (HPM) (Pender,
Murdaugh, & Parsons, 2006) will be considered as frameworks that could explain the
proposed interrelationships between some of the concepts in this study.

The Social Cognitive Theory
The SCT explains how changes in people’s behavior are attained and suggests

methods for promoting behavioral change (Bandura, 1977; 1986). Individuals are seen as

22

self-organizing, pro-active, self—reﬂecting and self-regulating. Human beings are
inﬂuenced by environmental forces or driven by concealed inner impulses. The SCT
posits that there is a dynamic interaction between human behavior, personal factors and
environmental inﬂuences, which is called reciprocal determinism (Bandura, 1977, 1986;
Pajares, 2002). There is a constant interaction between the three components, such that
individual behaviors are not merely seen as inﬂuenced by the environment, but the
environment is also, at least in part, amenable to modiﬁcations initiated by the individual.
All three behaviors, personal factors, and environmental inﬂuences, are acting on each
other simultaneously.

The concept of reciprocal determinism provides an opportunity to consider
multiple avenues to promote behavioral change (Baranowski, Perry, & Parcel, 2002;
Pajares, 2002). Interventions to encourage behavioral changes could be directed at any of
the three components of reciprocal determinism in SCT- personal factors, human
behaviors and environment (Bandura, 1986). Personal factors in the form of cognition,
affect, and biological events within the individual might be manipulated to promote
expected behavior (Pajares, 2002). Environmental factors also inﬂuence behavior. The
environment, described in SCT as those objective factors that can affect a person’s
behavior but that are physically and socially external to that person (Baranowski, et al.,
2002), includes family members, ﬁiends, peers, social norms and health system
characteristics.

Other relevant concepts in the SCT are “consequent determinants” and “outcome
expectations” (Bandura, 1977). Consequences determine behavior largely through their

information and incentive value. Observed or experienced consequences of a behavior

23

provide pertinent information that could cause an individual to continue or refrain from
that behavior. Human behavior is inﬂuenced not only by its immediate consequences but
also by anticipated consequences yet to be experienced. As much as women’s
experiences could inﬂuence their behaviors, observations of actions of others and its
consequences (whether positive or negative) could also inﬂuence women’s behavior.

In SCT, outcome expectation is deﬁned as a person’s estimate that a given
behavior, such as starting PNC, or not smoking nor drinking during pregnancy will lead
' to certain outcomes (e. g. healthy babies). In outcome expectations, individuals come to
believe that a particular course of action will produce certain outcomes (Bandura, 1977).
Bandura (1986) further recognized “human symbolizing” and “forethought capabilities”
as part of the factors that inﬂuence thoughts and subsequent actions. The concept of
human symbolizing capability incorporates the notion that people retain or discard
possible ideas/solutions or actions based on the estimated outcomes. However, to say that
people’s actions are informed by their thoughts of the outcomes or consequences does not
necessarily mean they are always objectively rational (Bandura, 1986). There are times
when people make faulty decisions, such as when they base their inferences on
inadequate information or fail to consider the full consequences of different choices.”
(Bandura, 1986, p. 19). However, the SCT is a rational behavior model but momentary
passions and emotions sometimes overrides our cognition and that is the part that SCT
doesnot address.

Health Promotion Model

The second guiding framework for this study is the Health Promotion Model

(HPM) (Pender et al., 2006). The model posits that individual characteristics and

experiences inﬂuence behavior-speciﬁc cognition and affect, and the eventual health-
promoting behavior (HPB), which is the endpoint or action outcome of the HPM. The
SCT and HPM are both concerned with the various factors within the individual and in
the environment that inﬂuence people’s actions. In the HPM, the individual
characteristics and experiences consist of two factors: (a) Prior related behaviors, such
as previous pregnancy experience; and. (b) Personal factors, including biologic factors,
such as age or BMI; psychological factors (e. g., perceived health status), or socio-cultural
factors, such as race, ethnicity, education, socioeconomic status and marital status. The
prior related behaviors and personal factors affect the health-promoting behavior
directly or indirectly through the behavior-speciﬁc cognition or affect (Pender et al.,
2006).

The HPM also emphasizes the importance of the behavior-speciﬁc cognitions and
affects, which address areas of potential effectiveness of nursing actions, because they
have a lot of motivational signiﬁcance. Hence, they are seen as the “core” for nursing
intervention. Among the behavior-speciﬁc cognitions and affects of the HPM are the
perceived beneﬁts of action, which are included in the HPM based on the assumption that
an individual’s decision to act in a particular way is based on the expected beneﬁt for
participating in the behavior. Perceived beneﬁts directly motivate behavior or they affect
the extent of commitment to a plan of action to engage in the behaviors from which the
anticipated beneﬁts will result (Pender et al., 2006). On the other side are the perceived
barriers to action, which can be thought of as including mental blocks, hurdles and
inconveniences that individuals recognize as being capable of preventing them from

practicing the behavior (Pender et al., 2006). Access to care, transportation, cost, and

25

other commitments are some examples of perceived or deﬁnitionbarriers to initiating
PNC.

Interpersonal inﬂuences. These are cognitions concerning behaviors, beliefs, or
attitudes of others, which may or may not correspond with reality, but are found to
inﬂuence people’s behaviors. Primary sources of interpersonal inﬂuence encompass
interactions and inﬂuences from family, peers, and health care providers (Pender et al.,
2006). Interpersonal inﬂuences include norms (expectations of signiﬁcant others), social
support (as examples, instrumental /tangible support, such as assisting with grocery
shopping or child care and emotional support in terms of encouragement to initiate and
continue PNC), and modeling (observation of others that are engaged in a particular
behavior. An example of norms is the familismo, in which individuals are expected to
practice some behaviors not for themselves but for the sake of the family (Pender et al.,
2006)

Finally the HPM proposes that all the above-mentioned factors are either directly
or indirectly related to a commitment to a plan of action, and the decision to initiate a
health-promoting behavior (e.g., initiating PNC, not smoking and not drinking during
pregnancy). The commitment to a plan of action however, could be inﬂuenced by
immediate competing demands that are not under the control of the individual and
preferences. For example a woman may only initiate PNC if she knows she is pregnant;
values the baby, PNC, and healthy outcomes; understands the relationship between PNC
and birth outcomes, and has no barrier or is supported to overcome barriers.

The SCT and the HPM provide a basic guide for explaining some of women’s

behaviors and actions after pregnancy recognition. But they are both less adequate as a

26

guide to understanding pregnancy decisions, in which emotions/affect plays such an
important role (Santelli, Speizer, Avery, & Kendall, 2006). They may also not be good
models for explaining the process of pregnancy recognition itself. However, they are
useful in explaining some of the changes in women's behaviors that may occur after
pregnancy recognition. Accordingly, the conceptual model for this study, which focuses
on the time after pregnancy recognition, will incorporate concepts and interrelationships,
using the SCT and HPM as the guiding framework.
The Conceptual Model and the interrelationships between the concepts

As the model in Figure 1 shows, the current study focuses on the following key
concepts: time of pregnancy recognition (PR), time of PNC initiation, number of PNC
visits, and birth outcomes, including gestational age at birth, birth weight, admission to
NICU and early infant death. The relationships represented by the solid arrows will be
examined. The variables in the double-lined boxes are the study main variables and the
single lined boxes contain the control variables. Therefore, the time of ﬁrst PNC and
number of PNC visits are possible intervening variables, but its relationship with birth
outcomes is being examined within the concept of time lag between pregnancy
recognition and initiation of PNC. Smoking and drinking behaviors are also possible

intervening variables. But they are examined only as control variables in this study.

27

  

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Pregnancy Recognition. This study deﬁnes pregnancy recognition as a one-time
experience of conﬁrming the existence of pregnancy. The time of pregnancy recognition
is, in principle, a continuous variable that spans throughout the expected human
gestational period of 40 to 42 weeks (Olds, London, Ladewi g, & Davidson, 2004).
Pregnancy recognition could occur early or late in the pregnancy. However, early
pregnancy recognition is deﬁned here as a woman's acceptance of the existence of the
pregnancy within the ﬁrst 6 weeks of gestation. Delayed or late pregnancy recognition
refers to such acceptance occurring only after the ﬁrst 6 weeks of gestation (6.1 weeks
and above).

Prenatal Care. This study examines PNC in terms of the time of initiation of PNC
and number of PNC visits. The time of initiation of PNC occurs during the prenatal
period, which corresponds with the expected gestational duration of 40 to 42 weeks.
Early PNC initiation is deﬁned as the initiation of PNC within the ﬁrst trimester (12
weeks) of pregnancy (Williams et al., 2006). Late PNC initiation is the initiation of PNC
after 12 weeks of gestation.

Time lag between Time of Pregnancy Recognition and PNC Initiation. The time
lag between time of pregnancy recognition and PNC initiation refers to the difference in
the time between these two events. Therefore the time lag is the time of PNC initiation
(PNC) minus the time of pregnancy recognition (PR). PNC — PR = Time lag. Figure 2
shows a diagrammatic presentation of the relationship (see Appendix A). Some of the
factors that affect time of PNC initiation account for the possible time lag between the
times a woman recognized her pregnancy and when she initiated PNC. Independent of

the time of pregnancy recognition, this study examines whether the time lag is associated

29

with variations in birth outcomes.

Birth outcomes. Birth outcomes,are deﬁned as the state of the child at birth,
during the neonatal and post-neonatal period. These outcomes are also indicators of
pregnancy outcomes. Birth outcomes in this study refer to the gestational age at birth,
birth weight, occurrence of NICU admissions and incidence of infant mortality.

Gestational age is dichotomized in terms of preterm and term births. Preterm birth
is the birth of an infant before the completion of 37 weeks of gestation (IOM, 2006).

The second outcome examined is the birth weight. Birth weight will be
dichotomized into the two categories of LBW (<2500 grams) and normal birth weight
(2500+grams) (World Health Organization (WHO), 1993). LBW frequently occurs with
infants born too early (i.e., preterm births), but sometimes is also present in infants born
to term, i.e., with fetal or intrauterine growth restriction (Farley, Mason, Rice, Habel,
Scribner, & Cohen, 2006; Goldenberg & Culhane, 2007). Low birth weight has been
described as a useful indicator of women’s reproductive health. While preterm birth is not
the same as LBW, a relatively high percentage of preterm babies are also LBW babies
(Mattison, Damus, Fiore, Petrini, & Alter, 2001).

The third outcome is the NICU admission. NICU admission shows the general
condition of the baby at birth. Babies whose physiological ability to function
independently at birth is compromised, usually need NICU admission. NICU admission
is deﬁned as the admission of a baby into the neonatal intensive care unit during the
' neonatal period, i.e., anytime between birth and the 28th day of life.

The fourth outcome is infant mortality. The infant mortality rate is also a global

measure of quality of care during pregnancy, labor and the neonatal period. Infant

30

mortality is deﬁned as the death of a baby between birth and one year of age.
Relationship between the Theories Guiding the Study and the Concepts in the Model

As mentioned earlier, human behavior, personal factors and the environment
interact with each other (Bandura, 1986). The primary human behavior of interest in this
study is the act of initiating PNC,,Thus pregnancy recognition, is taken to be a ‘given’ or
personal factor within a woman that could inﬂuence the woman’s perception of her
health status,precipitate a change in unhealthy behaviors, and initiate the practice of
healthy behaviors during pregnancy starting with the ﬁrst PNC visits. In addition, the
concept of consequent determinant and outcome expectations in SCT can be related to a
woman’s expectation of having a positive outcome, for example desire for a healthy child
could inﬂuence women’s prenatal behaviors (Alvik, et al., 2006).

Alternatively, the HPM provides further explanations for the relationship between
pregnancy recognition and PNC initiation. Individual experience of pregnancy
recognition could give women the impetus, through perceived beneﬁts of PNC, to initiate
PNC early. For example, the ﬁrst time experience of pregnancy may make some women
with their ﬁrst pregnancies feel that they do not have sufﬁcient information to live a
healthy lifestyle during pregnancy. Therefore, ﬁrst time mothers might be motivated to
initiate PNC early due to their perceived beneﬁts of getting necessary prenatal teaching
and counseling early in pregnancy. Studies have shown that early initiation of PNC is
inﬂuenced by the importance assigned to receiving PNC (Daniels et al., 2006;
Gazmararian, Arrington, Bailey, Schwarz, & Koplan, 1999; Mikhail, 1999). In this study,
it will be examined if nullipara (no prior birth) women are more likely to feel that PNC

could be helpful. Thus, it is assumed that the average perceived beneﬁts of PNC should

31

be greater among women with no prior birth and they may tend to initiate PNC earlier
than women with one or more prior children.

In general, in the study the time of pregnancy recognition is considered as. the
primary (potential) predictor of health-promoting behaviors during pregnancy. According
to the HPM, health-promoting behaviors are those behaviors that move individuals and
populations towards a state of optimal health (Pender et al., 2006). Health-promoting
behavior in this study is initiating PNC within the ﬁrst trimester of pregnancy. It does
not sufﬁce, however, just to initiate PNC; it is also necessary to continue PNC attendance
after the ﬁrst visit in order to have better birth outcomes (Williams et al., 2006). In
addition, the number of PNC visits has been associated with the gestational age at PNC
initiation (Petrou et al., 2001). Therefore, the probability of initiating PNC by 12 weeks
of gestation and the number of PNC visits are considered as intermediate outcomes of the
time of pregnancy recognition in this study. There is strong evidence in the literature that
maternal smoking and drinking behaviors predict birth outcomes. Thus, periconceptional
and prenatal behaviors such as not smoking and not drinking during pregnancy will be
examined as other variables that could inﬂuence birth outcomes (see Fig 1.).

As mentioned, the HPM model considers barriers to actions. Examination of the
relationship between perceived and actual barriers to early initiation and continued use of
PNC such as delayed clinic appointment; insurance and type of insurance coverage; long
clinic wait times; and unintended pregnancy were not the focus of this study. In this
study, a relevant barrier that can be examined empirically is the type of insurance
coverage a woman has. Furthermore, the environment is considered to include the social

and interpersonal interactions that potentially inﬂuence women’s prenatal behavior and

32

time of PNC initiation (Bennet et al., 2006; Dudgeon & Inhom, 2004; Logsdon & Davis,
2003; Schaffer & Lia-Hoagberg, 1997). While direct measures of the inﬂuence of the
social environment are not available, certain proxies, like women’s marital status or
race/ethnicity will be used as control for the effect of interpersonal inﬂuences on the time
of PNC initiation. Marital status shows whether a woman currently has a partner or
signiﬁcant other that could be a source of strong inﬂuence on her prenatal behaviors
including time of PNC initiation.

The conceptual model for this study extends beyond looking at the relationship
between time of pregnancy recognition and PNC. In addition, this study sets out to
examine the time of pregnancy recognition as a predictor of birth outcomes. There are
some additional factors within the environment that could affect the relationship between
the time of pregnancy recognition and birth outcomes. The main factors that might
confound the relationship between the time of pregnancy recognition and birth outcomes
include smoking and drinking behavior during pregnancy, maternal age, pre-pregnancy
BMI, nutritional habit, race and ethnicity, plurality (having more than a single birth)
(Alvik et al., 2006; Cedergreen, 2004; Chang et al., 2003; Haas et al., 2005; Raatikainen '
et al., 2006). Thus, factors such as plurality, smoking and drinking behavior during
pregnancy, maternal BMI, race and ethnicity will serve only as controls in the data
analysis. The time of pregnancy recognition will be examined as predictive of birth
outcomes.

In summary, the main objective of this study is to ﬁll gaps in nursing studies by
identifying the interrelationships between time of pregnancy recognition, time of PNC

initiation, number of PNC visits, and listed birth outcomes. This study differs from earlier

33

studies in that it uses current population-based data. It is also expected that the ﬁndings

will, for the ﬁrst time, provide information on whether birth outcomes are inﬂuenced by

the time of pregnancy recognition. Questions raised in this study will lay the groundwork

for future research in the area of pregnancy recognition and birth outcomes.

'Based on. this review of existing studies, the following research hypotheses were

postulated for the study:

Hypotheses

1)

2)

3)

4)

5)

Early recognition of pregnancy increases the probability that a woman will
participate in PNC.

Early recognition of pregnancy increases the probability of early initiation
of PNC, particularly among nulliparas.

Among women who participate in PNC, early recognition of pregnancy is
associated with higher numbers of total PNC visits.

Among women who participate in PNC, both a later time of pregnancy
recognition and a longer time lag between the time of pregnancy
recognition and the time of initiation of PNC are associated with adverse
birth outcomes such as prematurity (gestational age below 37 weeks),
LBW (birth weight below 2500 grams), admission into NICU, and infant
mortality.

Among women who had no prior birth (nullipara), early recognition of
pregnancy tends to have a greater positive effect on birth outcomes, such
as prematurity, LBW, admission to NICU, and infant mortality than

among women who had given birth to one or more prior children.

34

CHAPTER 3
Methodology

Research Design

This study is a secondary analysis of ﬁve annual data cohorts (2000-2004)
collected through the Pregnancy Risk Assessment and Monitoring Surveillance
(PRAMS) program in the US. The PRAMS is a population-based survey that is part of
the Centers for Disease Control and Prevention (CDC) initiative to reduce infant
mortality and LBW (Williams et al., 2006). The PRAMS program entails annual cross-
sectional surveys, which address a wide range of maternal behaviors and experiences that
occur before, during, and shortly after pregnancy among US women of childbearing
age. The data are representative of resident women of childbearing age in 29 US. states
who had live births between 2000 and 2004 within 2 to 6 months prior to being
contacted. The statistics of the participating state is as presented in Appendix B
Overview of PRAMS

The PRAMS is one of the CDC’s on-going population-based survey systems that
collect information on maternal characteristics, behaviors, and experiences that occur
several months prior to conception, during pregnancy, and post delivery. The PRAMS
was developed in response to distressing statistics on infant mortality and LBW
(Williams et al., 2006). The PRAMS survey data offer a supplement and are linked to
birth certiﬁcate information and provide participating project areas with information
speciﬁc to their jurisdiction, which can be used to plan and evaluate maternal and child
health programs and make health policy decisions. All PRAMS data are obtained by the

states.

35

Sample and Setting

The data used for this study are the PRAMS phase 4 national data for the years
2000-2004. Being a multi-state and multi-year data set, the total combined sample size
contains 157,692 respondents. Due to missing information on key variables, the ﬁnal
analysis sample used in this study comprises 136,373 survey respondents (for details, see
chapter 4). PRAMS surveys of women who deliver live-bom infants, cover a wide range
of maternal behaviors and experiences that may occur before, during, and shortly after a
pregnancy. Natality information, collected by each state’s Ofﬁce of Vital Records and
Health Statistics, is used as the sampling frame.

The PRAMS target population consists of mothers who are residents in the 29
states that participated in the study. Table B in appendix B provides a list of all the
participating states. When compared with the estimated number of women who had a
child in the US. in the year studied, the PRAMS women are about 48% of the total
women who had a child in those years in the US. To be eligible, women need to have a
live-bom infant delivered during the preceding 2 to 6 months. Prospective respondents
are randomly selected from state ﬁles of birth certiﬁcate records, using stratiﬁed
systematic-sampling with a random starting point. Stratiﬁcation permits both separate
estimates of subgroups of interest and comparisons across these subgroups. All states
oversampled women who had prior adverse pregnancy outcomes such as LBW (Williams
et al., 2006). Other criteria for stratiﬁcation and oversampling include: minority
race/ethnicity (Alaskan nativity, Non-Hispanic Black), and geographical location (urban

areas, populations > 25,000 versus rural).

36

Women, who had a record of being mentally incapacitated, had died, or had
multiple births for more than three gestations were excluded from the sampling frame.
This was deemed necessary because mentally incapacitated or impaired individuals might
not be able to give accurate information and quadruplets or giving births to ﬁve or more
babies in a single delivery are most likely to be LBW.

The LBW among these babies is not necessarily due to risk factors that are
pertinent to epidemiologic studies and, being aware of the possible complications
associated with multiple gestations, such mothers are also most likely to have received
more than the usual PNC.

The PRAMS data are derived from three sources: birth certiﬁcate data,
operational data (information on PRAMS data collection process, number of attempts to
contact participants and response rates), and questionnaire data.

1) The birth certiﬁcate data provide the sampling frame ﬁom which births are
stratiﬁed and then randomly selected for PRAMS surveillance. Birth certiﬁcate
information is also used to weight PRAMS survey data so that it is representative
of the population and serve as a source of demographic and clinical information
about the sampled mother and the infant.

2) The questionnaire data is the self-reported data that are collected by mail, and if
there is no response by mail, mothers are also contacted by telephone to reduce
non-response rate.

3) The operational data are used to calculate response rates based on the information
received about recruitment and data collection process. The operational data are

also to monitor the quality of operations and used for analysis of PRAMS survey

37

methodology.

All three sources of data are combined to create a ﬁnal, weighted PRAMS
analysis data set.
PRAMS Data Collection Procedure

The PRAMS survey utilizes a combination of mail and telephone survey
methodology to maximize response rates. Mailing is the primary form of data collection
in the PRAMS survey because of the ready access to mailing addresses and the cost
effectiveness of using mail surveillance. Each participating state samples between 1,300
and 3,400 women per year. Women are ﬁrst notiﬁed of the PRAMS survey and then sent
the questionnaire by mail. If the mother does not respond after three attempts by mail, she
is then contacted by telephone and has the opportunity to participate in the PRAMS
survey via telephone. Telephone follow-up for women who did not respond to mail
generally increases the overall response rate. Mailing is usually initiated within two to
three months after delivery. Data collection usually takes place within 95 days of being
contacted, which means that the infants are about six months old then. To reduce recall
bias, no questionnaires completed after nine months of delivery are accepted. Data
collection procedures and instruments are standardized to allow comparisons between
states. PRAMS questionnaires are available in both English and Spanish. Because the
PRAMS survey employs a mixed-mode methodology, two types of questionnaires are
available; the self-administered and interviewer-administered questionnaires (CDC,
2005)

The self-administered questionnaire is used with the mailing packets, and an

interviewer-administered questionnaire is used with the telephone phase. The

38

interviewer-administered questionnaire contains the same questions that are on the self-
administered questionnaire; however, some questions have been formatted differently to
facilitate the different mode of administration. The overall response rates for the states
that participated in PRAMS survey for 2001 ranged from 68% to 84% (median response
rate = 76%) with the exception of New York City at 49%. On the whole, most (91%) of
the states that participated in PRAMS achieved response rates of 70% or higher
(Shulman, Gilbert, & Lansky, 2006).

Protection of Human Subjects

Data Sources. The data for this study come from the PRAMS multi-state dataset.
Access to the PRAMS dataset for years 2000 to 2004 was given after the approval of a
proposal was granted both by the CDC and each state, whose data are included in the
dataset. This proposal was also submitted to the institutional review board for Michigan
State University (MSU) and approval was given to conduct the current analysis. All
requirements for human subjects’ protection and the necessary certiﬁcation administered
by the MSU Biomedical and Health Institutional Review Board (BIRB) were maintained
throughout this study.

This study is a secondary data analysis and does not involve any direct contact
with human subjects. There are also no personal identiﬁers in the PRAMS data set.
PRAMS participants were given incentives or rewards depending on the state’s choice.
The incentives and rewards given to participants included prepaid long-distance calling
cards, postage stamps, gift certiﬁcates for local retailers, sachets, picture frames, baby
bibs, coupons for certiﬁed birth certiﬁcates and participation in a cash reward rafﬂe

(CDC, 2005).

39

Instruments

The PRAMS questionnaire is available in English and in Spanish (Williams et al.,
2006). Not all states implemented the Spanish version ( e.g., Michigan). The
comprehensiveness of the PRAMS questions make it especially useﬁrl for states in
designing programs and developing policies to reduce infant mortality, LBW, and other
adverse pregnancy outcomes (Rogers, Ahluwalia, & Melvin, 1998).

The PRAMS questionnaire consists of two parts. First, there are core questions
that appear on all states’ surveys. Topics addressed in the PRAMS core questionnaire
include barriers to and content of prenatal care, obstetric history, maternal use of alcohol
and cigarettes, physical abuse, contraception, economic status, maternal stress, and early
infant development and health status. Second, there are state-added questions that are
tailored to each state's needs. There are two types of state-added standard questions.
Some standard questions provide additional information on topics already addressed in
the core questionnaire, including content of prenatal care, contraception, and physical
abuse. Other standard questions address different topics, including social support and
services, mental health, and injury prevention. A copy of the PRAMS core questionnaire
is part of the Appendices (see Appendix C).

Measurement qualities. The PRAMS survey uses a l4-page questionnaire with
core and state-speciﬁc questions on various topics and has been shown to have good
acceptability and response rate. This is measured by the item completion rate and burden
of measurement. On average, only 2.5% of questionnaires from 1996 PRAMS were less
than 95% complete (Gilbert, Shulman, Fischer, & Rogers, 1999). The burden of

measurement is assessed using the time necessary for completion, degree of

40

concentration required or degree of difﬁculty. The PRAMS questionnaire takes
approximately 20 minutes to complete (Shulman et al., 2006). This provides a minimal
respondent burden when answering the questions. With sample drawn monthly, newly
delivered mothers are asked to respond to questions within 2 to 6 months of delivery to
limit recall bias.

Being a population-based dataset, PRAMS data are weighted so that the results
can be generalized to an entire State’s population of women having a live birth (W illiarns
et al., 2006). The use of standardized data collection method also allows for comparisons
of results among states.

Evaluating reliability is difﬁcult for two reasons. First, most measures in the
PRAMS survey rely on single indicators for a single construct. Thus, internal consistency
of multiple indicators cannot be examined Second, it is not possible to assess the
temporal stability (test-retest reliability) of the PRAMS questionnaire either because the
cross-sectional survey 3 are based on different samples of respondents each year.

The birth certiﬁcate data that are used in the PRAMS also have some reliability
issues that should be carefully considered. A study by Dobie, Baldwin, Rosenbalt,
Fordyce, Andrilla, and Hart (1998) on the inter-rater reliability of birth certiﬁcates using
the kappa statistic reported low reliability of prenatal visits, prenatal care, and maternal
complications recorded on birth certiﬁcates compared to chart data in 1,937 low-risk
pregnant women in Washington. The discordance between the certiﬁcates and chart data
could be due to data entry error. To ensure accuracy and reduce errors, the National
Center for Health Statistics (N CHS) encourages all states to train and certify birth

certiﬁcate data collectors (Northam & Knapp, 2006). Another study that tried to

41

determine the reliability of the measurement of time of initiation of PNC compared
information from birth certiﬁcates and medical records. The study found using medical
record data to be the “gold standar ” that concordance for time of initiation of care was
80.2% and the kappa was 0.507 (DiGiuseppe, Aron, Ranbom, Harper, & Rosenthal,
2002)

The validity of the PRAMS questionnaire varies by item, since the items measure
different constructs. There is no report of criterion-related validity,. This is possibly due
to lack of a gold standard with which to compare many measures. As part of the efforts to
address the validity of PRAMS, several revisions or phases of the questionnaire have
been designed. Prior to the revision of the questionnaire, questions are evaluated for item
non-response, write-in responses, and whether respondents correctly followed the skip
patterns in the survey. Using these criteria, questions that perform poorly are revised
accordingly and pretested before being included in the questionnaire again.

The PRAMS data are based on women’s self-reports, and this increases the
possibility of biases. Although the bulk of the responses are self-administered
questionnaires mailed to respondents, a potential source of bias is interviewer bias, where
the respondents provide the response he or she believes would be appropriate. Recall
bias is another potential source of bias that may inﬂuence the PRAMS result. But in order
to address the problem of recall bias in the PRAMS, newly delivered women within 2 to
6 months of delivery are interviewed instead of the longer periods such as 5 years used in
other national survey such as the National Survey of Family Growth (N SFG).

Variables

The main outcomes examined in this study are time of ﬁrst PNC visit, total

42

number of PNC visits, gestational age, birth weight, admission to NICU and infant
mortality. The time of pregnancy recognition serves as the main predictor variable. The
“time lag” between the time of pregnancy recognition and time of PNC initiation is also
examined as a predictor of birth outcomes. The intervening variable is the time of ﬁrst
PNC visits to be measured within the concept of timelag. Some of the control and
confounding variables that will be considered include: age, parity, marital status, level of
education, insurance status, race/ethnicity, smoking and drinking behavior during
pregnancy, multiple births, prior birth outcomes such as prematurity and LBW,
prepregnancy BMI, and socio-economic status. The socio-economic status was measured
as whether or not a woman was on ANY public assistance program, such as WIC during
pregnancy, and source of income is from government aid) (see Figure 1).

Operational Deﬁnitions. The operationalization of the analysis variables in this
study is presented in Tables 1 to 3. These tables show the actual wording of the questions
from the PRAMS dataset that are used in this study. They also provide information on the
response categories and how they were coded for the analysis. A copy of the PRAMS

instrument is in Appendix C.

43

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49

Data Analysis

The data analysis for the hypotheses was conducted using binary and multinomial
logistic regressions (Agresti, 1996; Draper & Smith, 1998; Klein & Moeschberger,
2003). The analysis focused primarily on the six outcome variables, namely time of PNC
initiation, number of PNC visits, birth weight, gestational age, NICU admission and
infant mortality. Oneof the listed outcomes, time of PNC initiation, also served as
predictors (=intervening variables), but this is being measured within the concept of
timelag. These outcome variables include dichotomous categories (e.g., NICU admission)
and continuous outcomes (e. g., birth weight). Among the potential predictor variables for
these outcomes are continuous variables such as mother's age and categorical variables
such as marital status. The variables in the boxes with single borders in Figure 1 will be
examined as Confounding variables.

All analyses take into account the complex survey design to obtain correct point
and variance estimates. The PRAMS data sets contain information on the sampling
weights associated with each case/respondent; these weights are the inverse of the
probability of a case being sampled. They also contain information on the predetermined
strata, such as the states, within which the sampling process occurred. Using the ‘svy’
commands of the STATA statistical software: release 9, the information on sampling
weights, stratiﬁcation and clusters, can be incorporated via three types of estimators,
including linearization, balanced repeated replication and jackknife estimators, to provide
correct population estimates (STATA, 2005).

Given the very large sample size, the statistical signiﬁcance level has been set to a

cut-off point of p = 0.01. The combination of the four years data will be used for the

50

analysis. No trend analysis was conducted during this study. This is because the focus of
this study is to determine the current relationship between the key predictor variable and
the outcomes being examined.

Second, analytical variables in the PRAMS datasets were used for variables such
as time of pregnancy recognition and the time of PNC initiation, smoking and drinking.
The analytic variables for the time of pregnancy recognition and the time of PNC
initiation have been converted to reﬂect the same measurement units in weeks instead of
weeks and months. The analytic variables for smoking and drinking have been created
based on the combination of the series of questions asked in the core questionnaire about
drinking and smoking resulting in three response categories each ( see Table 3).

General preliminary analyses to determine the characteristics and distribution of I
the variables were conducted. These include assessment of the distributions of the
responses to key variables in the analysis, as well as an assessment of missing data
patterns. The data analysis started with an assessment of missing values and data cleaning
operations. Next, univariate analyses of the key variables were conducted including the
display of frequency distributions, and summary statistics such as population percentages,
means, medians and modes. These univariate analyses focus on identifying the basic
characteristics of all of the variables examined in this study.

For some analyses, the predictor variable, time of pregnancy recognition, and
some of the outcome variables that are continuous were recoded into categorical
variables. The recoded variables are: time of pregnancy recognition, participation in
PNC, time of PNC initiation, number of PNC visits, gestational age, and birth weight.

The time of pregnancy recognition was recoded into dichotomous categories--early

51

Table 3

PRAMS Response Categories and Coding for the Analysis

 

 

Variables PRAMS Code Code used for the analysis
Time of pregnancy Continuous Continuous: 1-43 weeks and
recognition = 1-138 Categorical:

weeks; recoded to 1- 43 (1-12 weeks = 1)

weeks (12.1 to 43 = 0)

0= “Late pregnancy recognition”

l= “Early pregnancy recognition”

Time of ﬁrst PNC visit = Continuous Continuous: 1-43 weeks
1-138 weeks; recoded to - Categorical:
1-43 weeks (1-12weeks=1)

(12.1 to 43 = O)

O = “Late PNC Initiation”

1: “Early PNC initiation”
Number of PNC visits Continuous Recoded to:

0 visits

< 11 PNC visits

11 to 15 PNC visits

> 15 PNC visits
Time lag between Not originally in Time of PNC - Time of PR
pregnancy recognition PRAMS created from

and PNC the PRAMS variables

 

52

Table 3 (continued)

 

Variables PRAMS Code

Code used for the analysis

 

Baby’s gestational age at Continuous

birth 0-77 weeks
. Birth weight Continuous
0-6435 grams
Admission to NICU

(Infant in ICU at birth) 1 = NO
2 = YES
Infant mortality (Infant 1 = NO

alive now) 2 = YES

Gestational age ranged between
22-43 weeks.
Recoded to
(22 to 36 weeks =1)
(37 to 43 =0)
l = “Premature Births”
0 = “Term Births”
Recoded birth weight:
(0 to 2499 grams =1)
(2500 to 6435 grams =0)
0 = “ Normal birth weight”
1 = “Low birth weight”
Recoded infant in ICU
1 = O = " Infant not in NICU "
2 = 1: " Infant in NICU "
recoded (2:0)
1 = " Infant not alive "

0 = " Infant alive "

 

53

Table 3 (continued)

 

Variables

PRAMS Code

Code used for the analysis

 

Age

Parity (Number of previous

live birth)

Marital status

Multiple Births (Plurality)

Continuous: 1 1-53

years

Continuous

0-18 and 26.

Categorical:
1 =Married
2=Other.
U=Unknown
Continuous

l to 5 births

Recoded as:

1 = “1 1-15 years”
2 = “16-20 years ”
3 = “21-25 years”
4 = “26—30 years”
5 = “31-35 years”
6 = “36-40 years”
7 = “41 years and above”
Recoded as:

O

1 and more
Recoded: 2 = O

0 = “ Not married”

1 = “Married”

Recoded as:
O = Twins or more

1: Single birth

 

54

Table 3 (continued)

 

 

Variables PRAMS Code Code used for the analysis
Level of education 1 = 0-8 yrs I = 0-8 yrs
2=9—11yrs 2=9-11yrs
3 = 12 yrs 3 = 12 yrs
4= 13-15 yrs 4:13-15 yrs
5=l6+yrs 5=l6+yrs
U=Unknown
Race/ethnicity I=Other Asian or Recoded as:

Paciﬁc Islander
2=White

3=Black

4=Am Indian
5=Chinese
6=Japanese
7=Filipino
8=Hawaiian
9=Other-Nonwhite
10=Alaska Native
(Used by AK only)

U=Unknown

0 = Non-Hispanic White

1 = Black

2 = American Indian or Alaska
Native

3 = Asian/Hawaiian or Paciﬁc
Islander

4 = Hispanic

 

55

Table 3 (continued)

 

 

Variables PRAMS Code Code used for the analysis
Socio-economic status 0 = Had no other public assistance
(consists of women on WIC 1 = Had other public assistance
during pregnancy, and

source of income is from

government aid).

Insurance status (Being on Merged Recoded as

Medicaid or not)

Prior Birth outcomes

Previous LBW

Previous premature births

responses from 4

questions to

create the
variable
I = NO
2 = YES
1 = NO
2 = YES

0 = No insurance

1 = Medicaid sometimes before or
during pregnancy

2 = Private insurance only

Recoded as:

l = O = Had no previous LBW

2 = 1 = Had a previous LBW

Recoded as:

1=0 = Had no previous premature birth

2=1 = Had previous premature birth

 

56

Table 3 (continued)

 

 

Variables PRAMS Code Code used for the analysis
Smoking Merged responses from 4 Recoded as :
questions to create the 0 = Non-smoker
variable 1 = Quitters and attempted quitters
2 = Continued smokers
9 = Missing
Drinking Merged responses from 3 Recoded as :
questions to create the O = Non-drinker
variable 1 = Quitters and attempted quitters
2 = Continued drinkers
9 = Missing
PNC Continuous variable on 0 visits = No Prenatal Care
participation number of PNC visits were 1 or more PNC visits = Had Prenatal
recoded into categorical Care
Prepregnancy Morbidly obese - BMI >40 Morbidly obese - BMI >40
BMI Obese - BMI 30-39 Obese - BMI 30-39

Overweight - BMI = 26-29

Normal weight - BMI_<_ 25

Overweight - BMI = 26-29

Normal weight - BMI: 25

 

57

(within 6 weeks) and late (after 6 weeks) pregnancy recognition (see Table 3).Time of
PNC initiation was also recoded into dichotomous categories-- early PNC initiation
(initiated PNC within the ﬁrst trimester (12 weeks of gestation) and late PNC initiation
(initiated PNC after the ﬁrst trimester (12.1 weeks and above). Numbers of PNC visits
were recoded into 3 categories (see Table 3). To determine women participation in PNC,
numbers of PNC visits were recoded into two categories (see Table 3). Gestational age
was recoded into premature births (gestational age at birth that is below 37 weeks of
gestation) and term births (gestational age at birth of 37 weeks and above). Birth weight
was also dichotomized into LBW (birth weight of 2500 grams and below) and normal
birth weight (birth weight above 2500grams). The recoding of the variables were done to
create clear-cut categories to easily identify

The analysis of the research hypotheses will be addressed as follows: For all
hypotheses the population estimates of the distributions of the outcome variable in
question will be displayed, followed by appropriately weighted regression models. All
regression models contain a standard set of (categorical and continuous) control
variables: parity, maternal age, marital status, level of education, insurance status, socio-
economic status (being on other public assistance), race/ethnicity, prior LBW, prior
premature birth. In addition, all models include the time of pregnancy recognition as a
major predictor variable. The regression models vary in terms of the choice of the
dependent variable and additional independent/intervening variables as speciﬁed in the
hypotheses. Regression diagnostics to examine the appropriateness of the model

assumptions are carried out.

58

CHAPTER 4
Results
Data 'Cleaning Missing or Misleading Data

The analysis sample was conﬁned to the years 2000 to 2004. The data contained
two cases for which the reported years of data collection were 1993 and 1999. These two
cases were removed from the analysis.

Most of the variables used in the data analysis were categorical, while some of the
continuous variables in the original dataset were recoded into categorical variables.
Frequency analyses revealed that none of the key variables used in the study had more
than 5% missing values. However, several data errors were discovered, such as outright
‘impossible’ values. For example, cases with a reported time of pregnancy recognition
and time of PNC initiation of more than 43 weeks were removed from the ﬁnal data
analysis, because the normal expected duration of a pregnancy is 40 to 42 weeks (Olds et
al., 2004). The total number of such responses of more than 43 weeks was 0.4% for the
time of pregnancy recognition and 1.3% for the time of PNC initiation. To ensure
consistency in the key variables such as gestational age, time of PNC initiation and time
of pregnancy recognition, additional cases had to be removed from the ﬁnal analysis.
These cases included responses that did not make sense or could not have been true.

Of the total sample, 7,645 (4.8% of the sample) cases with a negative time lag
between pregnancy recognition and PNC initiation were dropped from the analysis
sample, since a negative value implies that PNC initiation started before the recognition
of the pregnancy. Cases with a reported gestational age at birth that was smaller than the

time of PNC initiation were also treated as errors and were removed. For example, a

59

gestational age of 16 weeks at birth would be inconsistent with PNC initiation at 29
weeks after conception. There were 6,219 (3.9%) of observations with such discrepancies
in the data.

A further data problem arose with reported gestational ages that could not have
led to the birth of a viable infant. Thus, if the reported gestational age at birth was below
22 weeks, a case was removed from the analysis. Altogether, 808 cases were removed
from the analysis sample because gestational age was either missing or it was below 22
weeks or above 43 weeks.

Finally, when some of the variables with suspected mistaken responses were
examined with respect to several outcome variables, the other responses sometimes
showed that some error must have occurred, either in the responses or the imputation
process. For example, some babies with a reported gestational age at birth of 9 or 12
weeks were also recorded on the birth certiﬁcate as having been of normal birth weight
with no NICU visits. It is highly likely that, in such a case, the reported gestational age is
in error. All such cases with unreliable or inaccurate data implying logical inconsistencies
were removed from the ﬁnal analysis. The remaining cases, which were dropped, had
missing information on any of the key variables, namely total number of visits, birth
weight, admission into NICU, and infant mortality.

Overall then, a total of 21,3 19 (13.5%) cases were removed and treated as missing
in the data. Thus, the ﬁnal data set used for the analysis is based on 136,3 73 cases,
encompassing 86.5% of the total sample; when the population estimate was calculated for
this ﬁnal analysis sample, it is 88.4% of the population of newly delivered women in the

PRAMS states used for the study. All the statistics presented in this study are the

60

weighed analysis.
Recoding of Key Variables

From the responses to the original questions in the dataset, two new variables
were created: ( 1) “time lag” (i.e. the difference between the time of pregnancy
recognition and the time of PNC initiation) and (2) “being on public assistance other than
Medicaid” (WIC and government aid). Other variables used in the analysis were recoded,
generally into variables with fewer categories, as for example, smoking and drinking
behavior during pregnancy, Medicaid, or race/ethnicity. Information about PNC
participation was originally obtained from two data sources. If there were inconsistencies
between some survey responses and birth certiﬁcates, such that the women reported PNC
participation in the survey, but the birth certiﬁcate didn’t show this (or vice versa), it was
assumed that PNC participation occurred. In short, if women had at least one PNC visit
reported according to either source of information-the survey or the birth certiﬁcate- then,
the PNC visit variable in the other information source was recoded to “having
participated in PNC.”
Predictors of Missing Information

The analysis sample and the cases dropped from the study were compared to
examine whether there were any systematic differences between the two groups. Logistic
regression was used to examine — within a multivariate context - which variables would
predict whether cases would be excluded ﬁom the analysis due to missing information on
a key variable. The independent/predictor variables included in this analysis were the
main demographic variables, namely maternal age, parity, maternal level of education,

race/ethnicity and marital status. Table 4 provides a‘ descriptive comparison of the key

61

demographic characteristics of the sample used in the analysis, the sample of missing
cases as well as the total sample. For each group, Table 4 offers both the sample
percentages and the associated estimates of population percentages. The signiﬁcance tests
refer to the x2 or t-tests comparing the analysis sample to the sample of missing/excluded
cases. The p < 0.01 is the criteria for statistical signiﬁcance.

The multivariate analysis showed that three key variables were signiﬁcant
predictors of the odds of being missing, namely maternal race, marital status, level of
education, parity and maternal age. Speciﬁcally, being a minority (in comparison to non-
Hispanic Whites) increases the probability that a case is missing from the analysis
sample, as the following odds-ratios for minority populations show: Black (OR = 1.49, p-
value < 0001); American Indian or Alaskan Native (OR = 1.47 p-value < 0.001);
Asian/Hawaiian or Paciﬁc Islander (OR = 2.40, p-value < 0.001); and Hispanics (OR =
1.30 & p-value < 0.001). Women who are not married (OR = 1.26, p-value < 0.001) are
also more likely to be missing from the analysis.

Conversely, women with higher levels of education are less likely to be excluded
from the analysis sample, as indicated by the following odds, comparing women with
more education to women with 0 to 8 years of education: 9 --11 years of education (OR =
.67, p-value < 0.001); 12 years of education (OR = .51, p-value < 0.001); 13-15 years or
some college (OR = .38, p-value < 0.001 ); 16 years and above or College graduate (OR =
.31, p-value < 0.001). In short, with increasing levels of education there is a decrease in
the probability of being missing ﬁ'om the analysis. Age and parity were not signiﬁcant

factors in predicting missing status.

62

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65

Population Description

As indicated in Table 4, the mean age of women in the study population was 27.
The women were predominantly non-Hispanic White (65.6%), and married (67.1%). A
substantial (41.2%) percentage of this population of recently pregnant women was
nulliparas (had no prior birth). About 40% of the women had Medicaid sometime before
or during their pregnancy, and 44% were on public assistance (see Table 5). Fourteen
percent of the women continued to smoke during pregnancy, six percent drank sometimes
during their pregnancy and 56.8% either quit or attempted to quit drinking during
pregnancy.
Time of Pregnancy Recognition

Of the 5.5 million recent mothers to which the analysis sample can be
generalized, 72.4% (3,988,999 of the population estimate) recognized their pregnancy
early, which is to say, within six weeks of gestation (see Table 5). The modal time, when
women recognized their pregnancy, was at 4 weeks of gestation (25.7%), which is at the
point when most women miss their menstrual period. On average, women recognized
their pregnancy 5.9 weeks after conception (99% Conﬁdence Interval: 5.89 - 5.98), with
reported recognition ranging from 1 to 39 weeks. The median population estimate is 5
weeks. A large majority (92.5%) of the women had recognized. their pregnancy by 12
weeks of gestation. The mean for the time of pregnancy recognition is 4.13 weeks for
early recognizers (women who recognized within 6 weeks) and 10.64 weeks for late

recognizers (women who recognized their pregnancies after 6 weeks).

66

Table 5

Other Characteristics of the Analysis Population of 5,509.81 7 estimated postpartum
women

 

Characteristics: Population Estimate

(%) (99% CI)

 

Insurance status

No insurance 4.6 (4.33 — 4.83)
Had Medicaid 40.1 (39.59 — 40.69)
Private insurance only 55.3 (54.72 — 55.85)

Socio-economic status
Public assistance 43.5 (42.95 — 44.07)
No public assistance 56.5 (55.93 - 57.05)

Smoking Behavior

Non-smoker 73.4 (72.88 - 73.91)
Quitters 12.3 (11.95 — 12.73)
Continued smokers 14 (13.55 — 14.36)
Missing 0.3 (0.26 —- 0.38 )

Drinking Behavior

Non-drinker 36.7 (36.16 —— 37.26 )
Quitters 56.8 (56.19 —— 57.33)
Continued drinkers 6.1 (5.81 -— 6.38)
Missing 0.4 (0.37 — 0.52)

 

67

Table 5 (continued)

 

Characteristics:

Population Estimate

(%) (99% CI)

 

Time of pregnancy recognition

Mean (99% CI)

Mode

Median

Early Recognizers

Late Recognizers
Participation in PNC

No PNC

Had PNC
Frequency of PNC visits

0 visits

<11 visits

11-15 visits

>15 visits

Time of PNC Initiation (n = 5,485,923)

Mean (99% CI)

Mode

Median

Early PNC (512 weeks)

Late PNC (> 12 weeks)

5.9 weeks (5.89-5.98)
4 weeks

5 weeks

72.4 (71.88 -- 72.91)

27.6 (27.09 — 28.12)

0.4 ( 0.36 — 0.52)

99.6 (99.48 — 99.64)
Mean = 11.5 visits

0.4 (0.36 —- 0.52)

35.8 (35.22 — 36.30)

54.1 (53.55 — 54.70)

9.7 (9.34 — 10.03)

9 weeks (9.05 — 9.17)
9 weeks

8 weeks

79.9 (79.46 - 80.39)

20.1 (19.61 — 20.54)

 

68

As the main predictor variable in this study, the characteristics of women who
recognized their pregnancies early and those who recognized their pregnancies late are
discussed (the details are in Table 6). Within the group of women who recognized their
pregrancies early, by 6 weeks of gestation, the following characteristics were observed:
The mean age was 28 years and the women were mostly aged 26 to 30 years (29.5%).
About 74% were manied and 40.5% were women with no prior birth. Within the group
of women who recognized their pregnancies late (that is after 6 weeks of gestation) the
following characteristics were also observed: the women were mostly 21 to 25 years
(29.7%), unmarried (50.9%), and women with no prior birth (43.1%).

Comparison of the parity group revealed that it is only women with one prior
child who had higher percentage of early recognizers than late recognizers (34.5% vs.
29%, p < 0.001). The other parity groups (nullipara and women with two or more
children) had higher percentage of late recognizers than early recognizers. Among
women with four children and above, women who recognized their pregnancies late are.
almost twice the percentage of women who recognized their pregnancies early (see Table
6).

Compared to other race, the highest percentage (70.9%) of women who
recognized their pregnancies early was among non-Hispanic White (p < 0.001). Although
the highest percentage (51.4%) of the women who recognized their pregnancies late was
also among non-Hispanic White, this percentage is relatively less than the percentage of
women who recognized their pregnancies early. Of all the racial categories, the Black
race/ethnicity has the highest percentage (more than twice) of women who recognized

their pregnancies late than those who recognized early (25.3% vs. 12.5%,

69

Table 6

Characteristics of Women who recognized their Pregnancies Early and those who
recognized their Pregnancies Late

 

 

Characteristics Early Recognizers Late Recognizers p-value
n=3,988,999* 11: 1,520,818”
- % %
Age
Range 12-53 years 11-51 years
Mean 28 years 25.4 years
99% CI 27.91-28.06 25.27-25.54
< 0.001
11-15 years 0.3 1.4
16-20 years 11.1 25.00
21-25 years 24.1 29.7
26-30 years 29.5 21.5
31-35 years 24.4 14.2
36-40 years 9.3 6.9
41 years and above 1.3 1.3
Missing 0.02 0.00
100 100 <0.001

 

70

Table 6 (continued)

 

 

Characteristics Early Recognizers Late Recognizers p-value
n=3,988,999* r1= 1,520,818"
% %
Parity
0 40.51 43.07
1 prior birth 34.49 28.97
2 prior births 16.18 16.71
3 prior births 5.76 6.73
4 children and above 2.97 4.44
Missing 0.09 0.09
100 100 < 0.001
Socio-economic status
Public assistance 36.44 62.05
No public assistance 63.56 37.95
100 100 < 0.001

 

Note:* 72% of the population estimate; "28% of the population estimate

71

Table 6 (continued)

 

 

Characteristics Early Recognizers Late Recognizers p-value
n=3,988,999* 11: 1,520,818”
%
Race/ Ethnicity
Non-Hispanic White 70.94 51.41
Black 12.52 25.26
Hispanic 11.15 17.38
Others 4.52 5.13
Missing 0.87 0.82
100 100 < 0.001
Marital Status
Married 74.02 49.07
Not Married 25.92 50.89
Missing 0.06 0.04
100 100 < 0.001
Maternal education
Less than High School 13.21 28.63
High School 29.29 37.21
Some College or more 56.65 33.29
Unknown 0.85 0.87
100 100 < 0.001

 

*72% of the population estimate; “28% of the population estimate

72

Table 6 (continued)

 

Characteristics Early Recognizers Late Recognizers p-value

n=3,988,999* n= 1,520,818M

 

% %
Insurance status
No insurance 4.32 5.25
Had Medicaid sometimes
before or during pregnancy 32.67 59.74
Private insurance only 63.02 35
Missing 0 0.01
100 100 < 0.001
Smoking Behavior
Non-smoker 75.20 68.67
Quitters 12.05 13.08
Continued smokers 12.45 17.88
Missing 0.30 0.36
100 100 < 0.001
Drinking Behavior
Non-drinker 33.66 44.72
Drinkers 65.96 54.68
Missing 0.38 0.60
100 100 < 0.001

 

*72% of the population estimate; “28% of the population estimate

p < 0.001) (see Table 6).

The early recognizers group has more educated women who have had about 16
years of education or more (56.7%). More than twice of the women with less than high
school education recognized their pregnancies late compared to the early recognizers.
The highest percentages of the early recognizers were among nonsmokers (75.2% of the
analysis sample) and women who drank during their pregnancies (66%). Most of the late
recognizers were also on Medicaid (59.7%) (see Table 6).

An examination of the time of pregnancy recognition by the year of the interview
seems to indicate a trend towards greater early recognition: The population percentage of
early recognizers progressively increased with each subsequent year, except for 2004. For
example in 2000, 14.1% of women recognized their pregnancy early, 22.1% in 2001, and
26% and 28.4% in years 2002 and 2003 respectively.

Time lag between the Time of Pregnancy Recognition and the Time of PNC Initiation

The “time lag” (difference between the time of PNC initiation and the time of
pregnancy recognition) ranged from 0 to 38 weeks with a mean of 3.2 weeks (99% CI =
3.12 - 3.21). The comparison of the time lag between the early and late group revealed
that the mean time lag is longer among women who recognized their pregnancies early
(3.5 weeks, CI = 3.43 — 3.53) than women who recognized their pregnancies late (2.1
weeks, CI = 1.96 -— 2.15) (statistics not shown).

The bivariate analyses of the main variables and confounding variables in
hypothesis one to ﬁve were all signiﬁcant. Therefore, all the variables were included in

the subsequent multivariate analyses.

74

Hypothesis 1

The ﬁrst hypothesis to be tested in this study states that “Early recognition of
pregnancy increases the probability that a woman will participate in PNC. ” As the data
in Table 5 show, the percentage of women who had no prenatal care visits among the 5.5
million pregnant women to which the estimate refers is quite negligible (<1%). Still,
given the large sample size, it remained possible to examine, if early recognition would
increase participation in PNC.

The results from the multivariate logistic regression model conﬁrm. that there is
empirical support for the ﬁrst hypothesis (see Table 7). Aﬁer controlling for possible
confounding variables, such as age, parity, marital status, race/ethnicity, level of
education, insurance status, early recognition increases the odds of participation in
prenatal care. In addition, socio-economic status, using the weak measure of being or not
being on public assistance (apart from Medicaid) and prior birth outcomes (previous
LBW and prematurity) were also controlled for.

Table 7 shows that the odds of participating in PNC are signiﬁcantly higher
among women who recognized their pregnancy early (OR = 1.67), p-value <0.01 for all
the results. In addition to the time of pregnancy recognition, participation in PNC tends to
be signiﬁcantly higher among women with more than a high school education (OR =
2.3 5), among American Indians/Alaska Natives (OR = 2.28), and among women who had
private insurance (OR = 2.39). Unmarried and Black women had signiﬁcantly lower odds

of participating in PNC (OR = 0.46 and 0.48 respectively; p < 0.01).

75

Table 7

Logistic Regression Model Predicting Participation in PNC

 

Outcome: PNC Participation

Predictor variables: Odds Ratio (99% C1)

 

Pregnancy recognition (ref group: 0 = Late)

1= Early Pregnancy Recognition (5 6 weeks) 1'67 (1‘16 _ 2'41) *

Parity (ref group: 0 prior birth)

1 or more prior birth ' 0-74 (0-22 “ 2-47)

Marital Status (ref group: Married)
0.46 (0.28 -— 0.74)*

Unmarried

Level of education (ref group: < high school)

High School 1.39 (0.91 — 2.13)
> High School 2.35 (1.35 — 4.08)*
Age of mother (in years) 0.98 (0.94 — 1.01)

Race/Ethnicity (ref group: Non-Hispanic White)

Black 0.48 (0.31 -— 0.75)*
American Indian/Alaska Native 2.28 (1.07 — 4.86)* '
Asian 1.04 (0.38 — 2.85)
Hispanic 0.91 (0.52 — 1.62)

Previous Premature birth ( ref group: Yes)
No previous premature birth 1.24 (0.67 -— 2.27)
Previous LBW ( ref group: Yes had previous LBW))

No previous LBW 1-11 (0-64 ' 195)

 

*p < 0.01

76

Table 7 (continued)

 

Predictor variables:

Outcome: PNC Participation

Odds Ratio (99% c1)

 

Socioeconomic status (ref. group: No public assistance)

Public assistance

Insurance Status (reference group: No insurance)

Medicaid

Private Insurance

1.14 (0.65 — 2.02)

. 1.45 (0.79 — 2.68)

2.39 (1.16 — 4.94)*

 

Model Summary
F(19, 143314): 11.71
Prob > F: 0.0000
*p<001

77

Hypothesis 2

The second hypothesis states that “Among women who participate in PNC, early
recognition of pregnancy increases the probability of early initiation of PNC,
particularly among nulliparas. " Starting with this hypothesis and thereafter, the analysis
focuses only on the women who participated in PNC. These women represent 99.6% of
the analysis target population. The outcome variable for this second hypothesis is the
time of initiation of PNC, dichotomized into early (:12 weeks of gestation) and late (12+
weeks) PNC initiation.
Prenatal Care Initiation

As the data in Table 5 show, about 80% of the women initiated PNC early within
the ﬁrst trimester. The time that women initiated PNC ranged from 1 to 40 weeks. The
modal time when women had their ﬁrst PNC visit was at 9 weeks of gestation (14.6%).
On average women initiated PNC at 9 weeks (99% CI, 9.05 — 9.17). The median
population estimate is 8 weeks. Women, who initiated PNC early within 12 weeks of
gestation, were mostly between 26 and 30 years (29.2%), primigravidas (41.4%), married
(72.8%), Non-Hispanic White (69.9%), and more educated women who have had about
16 years of education or more (32.1%). Women who recognized their pregnancies early
(within 6 weeks of conception) have a mean of 7.6 weeks for time of PNC initiation.
Those who recognized later (after 6 weeks of conception) have a mean of 12.9 weeks
also. The highest percentage of women who recognized their pregnancy early initiated
PNC at 6 weeks (Table not shown).

The analysis was conducted in two stages. The dichotomous variable for the time

of pregnancy recognition was ﬁrst used as the only predictor variable in a logistic

78

regression model. This bivariate analysis revealed that early pregnancy recognition,
signiﬁcantly increases the odds of initiating PNC early (OR = 8.1, p- value < 0.01)
(statistics not shown). Next, the general multivariate analysis, as presented in Table 8,
shows the odds of having early initiation of PNC as predicted by the time of pregnancy

recognition independent of the effect of other confounding variables.

79

Table 8

Logistic Regression Model Predicting Early Initiation of PNC

 

Predictor variables:

Outcome: Early PNC Initiation

Odds Ratio (99% c1)

 

Pregnancy Recognition ( ref. group: 0 = Late )
1= Early Pregnancy Recognition

Parity (ref. group: 0 == 1 or more prior birth)
1: No prior birth (Nullipara)

Marital Status (ref. group: 0 = Married)
1 == Unmarried

Level of education (ref. group: less than high school)
High School
> High School

Age of mother (in log-years)

Race/Ethnicity (ref. group: Non-Hispanic White)
Black
American Indian/Alaska Native
Asian
Hispanic

Insurance Status (reference group: No insurance)
Medicaid

Private Insurance

6.05 (5.65— 6.47) *

1.23 (1.04 —1.46)*

0.765 (0.69 — 0. 82)*

1.32 (1.20— 1.45)*
1.65 (1.48— 1.85)*

2.03 (1.67 — 2.47)*

0.78 (0.71 — 0.85)*
0.84 (0.69 — 1.01)
0.68 (0.59 — 0.80)*

0.71 (0.64 - 0.79)*

1.70 (1.46 — 1.98)*

3.75 (3.21 — 4.38)*

 

*p < 0.01

80

Table 8 (continued)

Outcome: Early PNC Initiation
Predictor variables:

Odds Ratio (99% C1)
Socioeconomic status (ref. group: 0 = No public assistance)

1 = Public assistance 1.10 (1.00 - 1.22)

Previous LBW ( ref group: Yes had previous LBW)

No previous LBW 0.99 (0.85 — 1.15)
Previous Premature birth ( ref group: Yes)

No previous premature birth 0.79 (0.69 — 0.91)*

Model Summag
F(20, 144963) = 429.31

Prob > F = 0.0000

*p<001

81

As the results in Table 8 show, early pregnancy recognition signiﬁcantly increases
the odds of initiating PNC early (OR = 6.05, p-value < 0.01), after controlling for
demographics and prior birth outcomes among the population studied.

Table 8 also shows that the odds of initiating PNC early are signiﬁcantly higher
among nulliparas (OR = 1.23, p-value < 0.01). With increasing levels of education, there
are also higher odds of initiating PNC early: the OR for women with 16 years of
education was 1.65 (p-value <0.01). Likewise, among women who had Medicaid (OR =
1.70, p < 0.01) or private insurance (OR = 3.75, p-value <0.01), the odds of early
participation in PNC were signiﬁcantly larger than among uninsured women.

There is also a strong relationship between maternal age and the time of PNC
initiation. However, this relationship between maternal age and odds of the time of PNC
initiation was not linear; instead the logarithm of the maternal age provided the best ﬁt
and was used in the ﬁnal logistic model. (In subsequent analyses, the logarithm of the
maternal age was used, whenever it provided a better ﬁt than the linear term for maternal
age.) Table 8 shows that, with each unit increase in the log-years of the mother’s age,
the odds of initiating PNC early rise by more than 2 (OR = 2.03, p-value < 0.01). Since a
unit increase in the log-years refers to an ever larger linear interval at higher. values, this
ﬁnding suggests that an increase in mothers’ ages leads to higher odds of early PNC
initiation, but at a decelerating rate.

To examine the hypothesis that early pregnancy recognition has a particularly
strong effect on early PNC initiation among nulliparas, an interaction term involving
parity (at least one prior pregnancy vs. no prior pregnancy) and time of pregnancy

recognition (late vs. early) was introduced. However, this interaction term was not

82

signiﬁcant in the multivariate model (OR = 1.00, p—value = 0.96), indicating that the
effect of early pregnancy recognition on early PNC initiation does not differ between
nulliparas and women who have had one or more prior births (Table not shown).

In conclusion, the analyses show that early recognition of pregnancy increases the
probability of early initiation of PNC in women. When compared with women who have
had one or more prior births, nulliparas (women with no prior birth) have higher odds of
initiating PNC early. However, there is no empirical support for the second hypothesis
that early recognition of pregnancy increases the probability of early initiation of PNC
among to a greater degree among nulliparas than women who have had one or more prior
births.

Hypothesis 3

The third hypothesis states that “Among women who participate in PNC, early
recognition of pregnancy is associated with higher numbers of total PNC visits. ” The
outcome variable for this hypothesis is the total number of PNC visits. The outcome is
divided into three categories of less than 11 visits, 11 to 15 visits, and greater than 15
visits (see Table 5). This is because the American Academy of Pediatrics (AAP) and the
American College of Obstetricians and Gynecologists’ (ACOG) recommend 11 to 15
PNC visits. Pregnant women with the normal duration of pregnancy of 40 i 2 weeks are
expected to have 11 to 15 PNC visits (AAP & ACOG, 2002). Therefore, a multinomial
logit regression model was employed in this analysis and the 11 to 15 visits group was

used as the reference outcome category. Table 9 shows the results of this analysis.

Table 9

Multinomial Logistic Regression Model Predicting Frequency of PNC Visits (reference

category: 11-15 PNC Visits)

 

OR (99% C1)
Predictor variables: Odds of <11 visits

vs. 11 — 15 visits

OR (99% C1)
Odds of > 15 visits

vs. 11 — 15 visits

 

Pregnancy Recognition

(ref. group: 0 = Late )

1 = Early 0.71 (0.67 — 0.76)*
Parity

(ref. group: No prior birth)

1 or more prior birth 1.21 (1.07 — 1.37)*
Marital Status

(ref. group: Married)

Unmarried 1.15 (1.07 — 1.23)*
Level of education

(ref. group: < high school)

High School 0.82 (0.76 — 0.89)*

> High School 0.76 (0.69 — 0.73)*

1.17(1.05—1.29)*

1.07 (0. 90 -— 1.28)

1.02 (0.90— 1.15)

0.97 (0.84 — 1.12)

1.00 (0.85 — 1.17)

 

0 =11 to 15 PNC visits,p < 0.01

84

Table 9 (continued)

 

 

OR (99% Cl) OR (99% C1)
Predictor variables: Odds of <11 visits Odds of > 15 visits
vs. 11 — 15 visits vs. 11 - 15 visits

Age of mother

(ref group: 11-15 years)

16-20 years 0.63 (0.46 — 0.87)* 0.79 (0.43 — 1.44)

21-25 years 0.59 (0.43 — 0.81)* 0.82 (0.45 —— 1.51)

26-30 years 0.53 (0.38 -— 0.73)* 0.89 (0.48 — 1.64)

31-35 years 0.57 (0.41 — 0.79)* 0.96 (0.52 —- 1.78)

36-40 years 0.58 (0.42 — 0.81)* 1.05 (0.56 -— 1.97)

41 years 0.70 ( 0.48 — 1.04) 1.21 (0.59 — 2.46)

Race/Ethnicity (ref group: Non-Hispanic White)

Black 1.30 (1.21 — 1.40)* 1.12 (0.99 -— 1.27)
American Indian/Alaska Native 1.70 (1.45 — 2.00)* 1.02 (0.75 — 1.38)
Asian 1.39 (1.24 —- 1.56)* 0.83 (0.66 -— 1.03)
Hispanic 1.54 (1.41 — 1.67)* 0.98 (0.82 -— 1.16)

Socioeconomic status (ref. group: No public assistance)

Public assistance 0.96 (0.89 -— 1.03) 1.17 (1.04 —- 1.32)*
Insurance Status (ref. group: No insurance)

Medicaid 0.85 (0.75 — 0.97)* 1.08 (0.84 — 1.38)

Private Insurance 0.62 (0.55 — 0.71)* 1.05 (0.82 - 1.34)

 

0 =11 to 15 PNC visits,p < 0.01

85

Table 9 (continued)

OR (99% C l)

Predictor variables: Odds of <11 visits

vs. 11 — 15 visits

Previous LBW (ref. group: Yes)

No previous LBW 0.93 (0.83 — 1.05)

Previous Premature birth ( ref group: Yes)

No previous premature birth 0.94 (0.84 - 1.05)

Model Summg

F (54, 147655)

133.26
Prob > F

0.0000
0 =11 to 15 PNC visits,p < 0.01

86

OR (99% C1)
Odds of > 15 visits
vs. 11 — 15 visits

0.96 (0.79 — 1.17)

0.71 (0.59 — 0.84)*

Frequency of PNC visits. Half of the women in the study (54%) had 11 to 15
PNC visits (see Table 7). The mean number of visits was 11.5 visits and mode was 12
visits. Table 9 shows that the relationship between time of pregnancy recognition and the
numbers of PNC visits was signiﬁcant, even when the control variables are included in
the model. In particular, early pregnancy recognition is associated with lower odds of
having fewer than the recommended number of PNC visits and higher odds of having
more than the recommended PNC visits (OR of having < 11 visits = 0.71 and >15 visits =
1.17, p < 0.01).

Minority status is associated with having fewer than the recommended numbers of
PNC visits (OR of having < 11 visits for American Indian/Alaska Native = 1.70,
Hispanic = 1.54, Asian = 1.39, Black = 1.30). There are signiﬁcantly greater odds of
having a lower number of PNC visits among women who have had one or more prior
births (OR = 1.21, p—value <0.01), and unmarried women (OR = 1.15, p-value < 0 .01).
Older women have lower odds of having less than 11 PNC visits relative to younger
adolescents aged 11 to 15 years. Speciﬁcally, women aged ‘26 to 30 years have the lowest
odds of having < 11 PNC visits (OR. = 0.53, p-value < 0 .01) compared to adolescents
aged 11 to 15 years. Having insurance coverage, both Medicaid (OR = 0.85, p-value < 0
.01) and private insurance (OR = 0.62, p-value < 0 .01) is also signiﬁcantly related to
lesser odds of having less than 11 PNC visits compared to women who had no insurance
during pregnancy.
Hypothesis 4

The fourth hypothesis tested in this study states that “Among women who

participate in PNC, both a later time ofpregnancy recognition and a longer time lag

between the time of pregnancy recognition and the time of initiation of PNC is associated
with adverse birth outcomes such as prematurity (gestational age below 3 7 weeks), LBW
(birth weight below 25 00 grams), admission into NIC U, and infant mortality. " There are
four main outcomes used to test this hypothesis, namely gestational age at birth, birth
weight, admission into NICU and infant mortality. The following section presents a brief

descriptive analysis of the four main outcomes (see Table 10).

88

Table 10

Descriptive Analysis of the Birth Outcomes of the Analysis Population of 5, 509, 81 7

estimated postpartum women

(% or means)

 

Birth Outcomes (99% CI)
Gestational Age at Birth

Premature Births 8.9%

Term Births 91.1%

Mean 38.7 weeks

(99% CI) (38.69 — 38.72 weeks)
Birth weight

LBW 6.9%

Not LBW 93.2%

Mean 3326 grams

(99% C1) (3320 — 3331 grams)
NICU Admission

Yes 11.0%

No 89.0%
Infant Mortality

Yes 0.5%

No 99.5 %

 

89

Gestational Age at Birth. Of the 5.5 million estimated population of post-partum
women in the PRAMS states used for this study, Table 10 shows that 8.9% had
premature births (births before 37 weeks of gestation). The mean gestational age in this
study is 38.7 weeks (99% CI: 38.69 — 38.72). The gestational age at birth in this study
population ranged from 22 to 43 weeks. Over a quarter (25.6%) of the women with
premature births was 21 to 25 years old, and 42.4% were ﬁrst time mothers (nulliparas)
(see Table 11). Women aged 41 years and above had the highest percentage of premature
babies (12.2%), followed by young adolescents, 11 to 15 years old (11.6%). Women aged
26 to 30 years had the lowest percentage (8.1%) of premature births. Married women
were also less likely to have premature births than women who were not married (8.2%
vs. 10.3%) (statistics not shown in the table).

Birth weight. The mean birth weight of the babies for the population of recent
mothers in this study was 3,326 grams (99% C1: 3320 — 3331 grams) (see Table 10).
About seven percent of the women had babies with LBW. The mean weight of LBW was
1994 grams. The mean weight for non-LBW (N LBW) babies was 3429 grams
respectively. More than a quarter (26.2%) of the LBW babies was among women aged 21
to 25 years. The highest percentage (46.2%) of LBW babies was among nulliparas (Table
1 1). Compared with women who have had one or more prior births nulliparas had a
higher incidence of LBW (7.7 vs. 6.3, p < 0.001) (not shown in the table).

Neonatal Intensive Care Unit Admissions. Table 10 shows that 11% of all births
to the population of women in the study were admitted into the neonatal intensive care
unit (NIC U). The babies admitted into the NICU were more likely to have been born to

nulliparas (45.7%) (see Table l 1). Women with one prior birth had the lowest incidence

90

Table 1 1

Some Characteristics of Women Based on Birth Outcomes
Characteristics Term Birth* Preterm Births" p-value

% %

 

Gestational Age

Maternal Age
11-15 years 0.59 0.80
16-20 years 14.79 16.12
21-25 years 25.61 25.58
26-30 years . 27.54 25.01
31-35 years 21.67 21.02
36-40 years 8.56 9.74
41 years and above 1.22 1.74
Missing 0.01 0.00
100 100 <0.001
Marital Status
Married 67.64 61.96
Not Married 32.30 38.02
Missing 0.05 0.02
100 100 < 0.001

 

Note:* n = 5,020,771, 91.12% of the population estimate (PE); ** n= 489,047, 8.9% of
PE

91

Table 1 1 (continued)

 

 

 

Characteristics Term Birth Preterm Births p-value
n = 5,020,771* n= 489,047 **
% %
Gestational A ge
Parity
0 41.1 42.4
1 prior birth 33.3 29.7
2 prior births 16.4 15.8
3 prior births 5.9 7.1
4 children and above 3.2 4.8
Missing 0.1 0.1
100 100 < 0.001
Race/Ethnicity
Non-Hispanic White 66.04 60.49
Black 15.35 23.15
Hispanic 13.01 11.39
Others 4.72 4,34
Missing 0.88 0.63
100 100 < 0.001

 

Note:* n = 5,020,771 , 91.12% of the population estimate; ** n= 489,047, 8.9% of the

population estimate

92

Table 1 1 (continued)

 

 

 

Characteristics NLBW* LBW“ p—value
% %
Birth weight
Maternal Age
11-15 years 0.59 0.95
16-20 years 14.64 18.50
21-25 years 25.56 26.18
26-30 years ' 27.57 23.82
31-35 years 21.78 19.42
36-40 years 8.61 9.36
41 years and above 1.23 1.77
Missing 0.01 0.00
100 100 <0.001
Marital Status
Married 67.92 56.55
Not Married 32.03 43.41
Missing 0.05 0.05
100 100 < 0.001

 

Note:* n = 5,132,596, 93.15% of the population estimate (PE); ** n = 377,221, 6.85% of

PE

Table l 1 (continued)

 

 

Characteristics NLBW* LBW" p-value
% %
Birth wei t
Parity
0 40.85 46.17
1 prior birth 33.34 27.87
2 prior births 16.40 15.31
3 prior births 6.00 6.31
4 children and above 3.31 4.26
Missing 0.09 V 0.08
100 100 < 0.001
Race/Ethnicity
Non-Hispanic White 66.29 55.39
Black 15.15 28.17
Hispanic 4.68 4.79
Others 13.01 10.98
Missing 0.87 0.67
100 100 < 0.001

 

Note:*n = 5,132,596, 93.15% of the population estimate (PE); ** n = 377,221, 6.85% of
PE

94

Table l 1 (continued)

 

Characteristics No NICU admission* N ICU admission ** p-value

% %

 

Neonatal Intensive Care Unit Admission

Maternal Age
11-15 years 0.59 0.80
16-20 years 14.80 15.72
21-25 years 25.65 25.25
26-30 years 27.41 26.55
31-35 years 21.72 20.79
36-40 years 8.58 9.38
41 years and above 1.24 1.50
Missing 0.01 0.01
100 100 <0.001
Marital Status
Married 67.73 62.31
Not Married 32.22 37.64
Missing 0.05 0.05
100 100 < 0.001

 

Note:* n =— 4,903,812, 89% of the population estimate (PE); ** n = 606,006, 11% of PE

95

Table 1 1 (continued)

 

 

 

Characteristics No NICU admission* NICU admission ** p-value
% %
Neonatal Intensive Care Unit Admission
Parity
O 40.66 45.70
1 prior birth 33.41 29.31
2 prior births 16.51 14.84
3 prior births 6.00 6.24
4 children and above 3.32 3.82
Missing 0.09 i 0.08
100 100 < 0.001
Race/Ethnicity
Non-Hispanic White 66.51 57.76
Black 15.35 21.63
Hispanic 4.67 4.91
Others 12.61 14.99
Missing 0.87 0.71
< 0.001

 

Note:* r1 = 4,903,812, 89% of the population estimate (PE); ** n = 606,006, 11% of PE

Table 1 1 (continued)

 

 

 

Characteristics Infant Alive* Infant not Alive ** p-value
% %
Infant Mortality
Maternal Age
11-15 years 0.61 0.69
16-20 years 14.88 20.10
21-25 years 25.59 28.22
26-30 years 27.32 27.00
31-35 years 21.65 15.20
36-40 years 8.67 7.68
41 years and above 1.27 1.11
Missing 0.01 0.00
100 100 < 0.001
Marital Status
Married 67.21 51.89
Not Married 32.73 48.02
Missing 0.05 0.08
100 100 < 0.001

 

Note:* 11 = 5,481,788, 99.5% of the population estimate (PE); ** n = 28,029, 0.5% of PE

97

Table l 1 (continued)

 

Characteristics

 

 

Infant Alive* Infant not Alive ** p-value
% %
Infant Mortality
Parity
0 41.19 46.25
1 prior birth 32.99 26.89
2 prior births 16.33 15.54
3_ prior births 6.02 7.49
4 children and above 3.38 3.81
Missing 0.09 0.01
100 100 < 0.001
Race/Ethnicity
Non-Hispanic White 65.59 57.32
Black 15.98 27.40
Hispanic 12.88 11.56
Others 4.7 3.22
Missing 0.86 0.49
100 100 < 0.001

 

Note:* 11 = 5,481,788, 99.5% of the population estimate (PE); ** n = 28,029, 0.5% of PE

98

of admission into NICU when compared with women with two, three, four or more prior
births (9.8% vs. 10%, 11.4%, and 12.5% respectively; p < 0.01) (statistics not shown in
the table). Although the highest percentage of the babies admitted into NICU were born
to women aged 26 to 30 years (26.6%)(see Table 11), young adolescents were more
likely to have had babies admitted into NICU (14.4%) than the older women, such as
women aged 16 to 20 years (11.6%) and women aged 26 to 30 years (10.7%) (statistics
not shown in the table).

Infant Mortality. Of all the infants born to the women in the study less than 1%
were dead by the time the mothers were surveyed. Although the association between
maternal age and infant mortality was not signiﬁcant, of all the babies that died in the
study, infant mortality was highest (28.2%) among women aged 21 to 25 years.
Unmarried mothers had a higher percentage of infant mortality than married mothers
(0.7% vs. 0.4%, p < 0.01).

Table 12 presents the logistic regression models used to test the fourth hypothesis.

99

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The results provide empirical support for the hypothesized relationships between
early pregnancy recognition and all birth outcomes except for infant mortality (see Table
12). The possible confounding variables controlled for in the multivariate analysis are:
maternal age, race/ethnicity, parity, marital status, level of education, socio-economic
status measured as being on other public assistance (apart from Medicaid), incidence of
having multiple births (twins or more), drinking and smoking behavior during pregnancy,
previous birth outcomes (premature births and LBW babies), and prepregnancy BMI.
After controlling for the confounding variables, early pregnancy recognition signiﬁcantly
reduces the odds of having adverse birth outcomes namely, prematurity (OR = 0.91, p-
valuc < 0.01), LBW (OR = 0.93, p-value < 0.01) and NICU admission (OR = 0.89, p-
value < 0.01). This analysis further reveals that after controlling for possible confounding
variables, longer time lags between recognition and PNC initiation were, contrary to the
study hypothesis associated with reduced prematurity, (OR = 0.99, p-value' < 0.01), LBW
(OR = 0.98, p-value < 0.01) and NICU admission (OR = 0.99, p-value < 0.01). Early
pregnancy recognition and longer time lag was not associated with infant mortality.

Other predictors of adverse pregnancy outcomes include: older age, minority
racial group, smoking during pregnancy, having Medicaid sometime during pregnancy or
a mother’s prepregnancy BMI greater than 29 (see Table 12). There is an increase in the
odds of having NICU admission with each additional year to maternal age (OR = 1.02, p-
value < 0.01). There is also a strong but non-linear relationship between maternal age and
the odds of having premature births, and LBW babies. The logarithm of maternal age
provided the best ﬁt to explain the relationship for these two outcomes. Table 12 shows

that with each unit increase in the log-years of the mother’s age, the odds of having

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premature births and LBW babies increase (OR = 1.67 for premature births; OR = 1.80
for LBW babies, p-value < 0.01). This ﬁnding suggests that an [increase in mothers’ ages
lead to higher odds of having premature births and LBW babies, but at a decelerating
rate.

Black race/ethnicity was strongly associated with higher odds of having
premature births (OR = 1.45, p-value < 0.01), LBW babies (OR = 2.15, p-value < 0.01),
NICU admission (OR = 1.38, p-value < 0.01), and infant mortality (OR = 1.48, p-value <
0.01). Asian race/ethnicity was also strongly associated with prematurity (OR = 1.34, p-
value < 0.01), and LBW (OR = 1.22, p-value < 0.01), and Hispanics had a signiﬁcantly
higher odds of having NICU admissions (OR = 1.19, p-value < 0.01), than the non-
Hispanic Whites. A history of no previous premature birth (OR = 0.56, p-value < 0.01)
and being a drinker during pregnancy (OR = 0.52, p-value < 0.01) were associated with
reduced odds of infant mortality (see Table 12).

Continued smoking during pregnancy was strongly associated with higher odds of
having LBW babies (OR = 1.72, p-value < 0.01). Also among women who had Medicaid,
the odds of having LBW babies (OR = 1.17, p-value < 0.01) and having premature births
(OR = 1.29, p-value < 0.01) were signiﬁcantly larger than among uninsured women.
Being overweight/obese (BMI > 29) before pregnancy also increased the odds of having
NICU admission (OR = 1.30, p-value < 0.01) relative to being underweight before
pregnancy.

Hypothesis 5
The ﬁfth hypothesis in this study states that “Among women who had no prior

birth (nullipara), early recognition of pregnancy tends to have a greater positive effect on

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birth outcomes, such as prematurity, LBW, admission to NIC U, and infant mortality than
among women who had given birth to one or more children

This hypothesis was not supported by the data. The interaction effect between
being a nullipara and having early pregnancy recognition was not signiﬁcantly associated
with any of the birth outcomes such as prematurity (OR = 1.09, p—value = 0.15), LBW
(OR = 1.07, p-value = 0.16), NICU admissions (OR = 1.11, p-value = 0.07), and infant
mortality (OR = 0.59, p-value = 0.02). While being statistically insigniﬁcant, the OR
associated with the interaction effect was only less than 1 for infant mortality, which is to
say that, in accordance with the hypothesis, the efﬁcacy of early pregnancy recognition in
reducing infant mortality may, indeed, be somewhat larger among nulliparous women, ‘

but the interaction effect lacked the power to show it.

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CHAPTER 5
Discussion

This study was designed to determine the extent to which early recognition of a
pregnancy (conﬁrmed pregnancy within 6 weeks of conception) predicts early initiation
of PNC (start PNC within 12 weeks of conception) and the number of PNC visits. In
addition, the study examined how early pregnancy recognition affects birth outcomes
such as gestational age at birth, birth weight, rates of admission to NICUs and infant
mortality.
Prevalence of Early Pregnancy Recognition and Early Prenatal Care Initiation

Compared to 20 years ago, when studies reported 56% (N SFG) and 67.7%
(NMIHS) of women recognizing their pregnancy early (within 6 weeks of conception)
(Kost etal., 1998), the 2001 to 2004 PRAMS data show a higher percentage of women
recognizing their pregnancy early (72.4%). While Kost’s study was based on a nationally
representative sample, the PRAMS data used in this study represent the population of 29
states which is about 48% of the total women who had a baby in the US. (U. S Abstract,
2005), This increase in the proportion of women who recognized their pregnancy early
could be due to the fact that PRAMS is not so representative of the total US population.
The increase could also be due to the recent advances in technology of home pregnancy
testing that affords women the opportunity to test earlier in the convenience of their
homes (Morroni & Moodley, 2006).

According to the current PRAMS estimates, the peak time of pregnancy
recognition is at 4 weeks, which is congruent with the physiological expectation that

women usually miss their period around 4 weeks of their last menstrual cycle (Olds et al.,

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2004). Over 90% of pregnant women in 2001 to 2004 had recognized their pregnancy by
twelve weeks of gestation. This ﬁnding is relevant to the Healthy People 2010 goal that at
least 90% of women should get into PNC within the ﬁrst trimester (12 weeks) of
pregnancy.

The percentage of women who initiated PNC early (initiating care within the ﬁrst
trimester/ 12 weeks of pregnancy) was a bit lower with 80%. A somewhat smaller spread
between the percentage of women recognizing their pregnancy early (67.7%) and the
percentage of women initiating PNC early (60.1%) was reported by Kost et al. (1998).
Despite the fact that there is a longer cut-off point for the time of PNC initiation in the
PRAMS study compared to Kost’s (12 weeks vs. 8 weeks), there still is a drop off of 10%
of women who recognized their pregnancy early but did not initiate PNC within 12
weeks. This ﬁnding suggests that some women delay the initiation of PNC after the
recognition of the pregnancy. It also reinforces the notion that women’s behaviors are
inﬂuenced not only by the biologic factors around them but also by various factors in the
environment (Bandura, 1986) and the perceived beneﬁts of their actions (Pender, et al.,
2006)

Similar to the percentages reported in another study that presented the 2003
PRAMS result for the State of Michigan (MDCH, 2005), the percentage of women who
had no PNC was negligible. It appears that relatively few pregnant women in the United
States do not at all avail themselves of PNC or lack access to it. Even so, an estimated
22,000 pregnant women (= 0.4%) went without PNC in the 29 states covered by the

PRAMS data.

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Consequences of Early Pregnancy Recognition

Among the ﬁve hypotheses postulated about the relationship between early
pregnancy recognition and the intermediate and ultimate outcomes examined in this
study, some hypotheses were conﬁrmed, others were not (see Table 13).
Time of Pregnancy Recognition as Predictor of Participation in PNC

. As hypothesized, women who recognized their pregnancy early had signiﬁcantly
higher odds of participating in PNC. This greater tendency to participate in PNC among
women who recognized their pregnancies early could be due to the stimulating effect of
pregnancy recognition. Pregnancy recognition may be viewed as one of the personal
factors within an individual, which, according to the Social Cognitive Theory (SCT)
(Bandura, 1986), eventually inﬂuence the behavior of those participating in PNC.

Other strong predictors of participation in PNC include a higher level of education
(16 years or above); having private insurance; and being American Indians/Alaska
Natives (AI/AS). A higher level of education is often associated with a higher socio-
economic status, including a higher income and necessary ﬁnancial support needed for
getting PNC. While the analysis included a simple measure of income (receiving public
assistance versus not receiving it), this measure did not take into account the whole range
of income found within the population and, thus, provides imperfect statistical ‘control’
of income as a confounding variable.

Contrary to ﬁndings based on the 2000 to 2004 PRAMS data, a secondary data
analysis of all states in the US. by Grossman, Baldwin, Casey, Nixon, Hollow, and Hart
(2002) revealed that American Indians/Alaska Natives in most states in the US. have a

higher rate of “inadequate” PNC (that is initiated PNC in the third trimester) than White.

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Table 13

Predictive Eﬂect of Early Pregnancy Recognition on the Intermediate and Ultimate
Outcomes in the Study

 

Hypothesis Hypothesis Statement Predictive Effect

 

1 Early recognition of pregnancy increases the probability Conﬁrmed

that a woman will participate in PNC

2 Early recognition of pregnancy increases the probability of Conﬁrmed
early initiation of PNC, particularly among nulliparas partially
3 Among women who participate in PNC, early recognition Confumed

of pregnancy is associated with higher numbers of total
PNC visits

4 Among women who participate inPNC, both a later time Conﬁrmed for
of pregnancy recognition and a longer time lag between prematurity, LBW
the time of pregnancy recognition and the time of and NICU
initiation of PNC is associated with adverse birth admission; not
outcomes such as prematurity (gestational age below 37 conﬁrmed for
weeks), LBW (birth weight below 2500 grams), admission infant mortality.
into NICU, and infant mortality

5 Among women who had no prior birth (nullipara), early Not Conﬁrmed
recognition of pregnancy tends to have a greater positive
effect on birth outcomes, such as prematurity, LBW,
admission to NICU, and infant mortality than among

women who had given birth to one or more prior children

 

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The study by Grossman et al. (2002) reported just rates of ﬁrst trimester PNC and did not
control for any confounding variable

One possible explanation for the difference in the result of this current study and
that of Grossman et al. (2002) could be a real change in early PNC use by American
Indians/Alaskan Natives between 1989 to 1991, to which Grossman’s study refers and
this analysis, which used the more recent data from 2000 to 2004. Again, it is unlikely
that the use of a national dataset (Grossman) versus a dataset covering ‘only’ 29 states
explains the difference. This can be seen from Grossman’s reports on state-speciﬁc
results, which show that four states recorded lower rate of “inadequate” PNC (initiated
PNC in the third trimester) among Al/AS than for Whites. The ﬁndings in these four
states are similar to the ﬁndings in this study. The Healthy People 2010 goal and general
health system in United States is geared towards reducing health disparities, and there
have been different interventions to address this. The different ﬁnding in this study on the
AI/AS minority group could also be due to the effect of the various interventions to
reduce health disparities in the nation.
Time of Pregnancy Recognition as Predictor of Early PNC Initiation

It is not sufﬁcient to examine women’s participation in PNC; it is also important
to examine the relationship between time of pregnancy recognition and the speciﬁc time
of PNC initiation. This is because the time of PNC initiation provides deﬁnite
information about whether the woman started care early or not; thus, helping to determine
the quality of care (IOM, 2001). This study conﬁrmed that, when women recognized their
pregnancy early, the odds of also initiating PNC early rise substantially, namely by a

factor of more than 6, after controlling for sociodemographic characteristics, having

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multiple births and prior birth outcomes. This ﬁnding is similar to earlier reports on the
relationship between pregnancy recognition and PNC initiation (Blackwell, 2002; Kost et
al., 1998). Blackwell (2002) concluded that pregnancy realization was a major impetus
for women to initiate PNC. Kost (1998) also identiﬁed early pregnancy recognition as a
strong predictor of early PNC. Analysis of 1997 PRAMS data for 13 states, and 1989 to
1997 birth certiﬁcate for all 50 States in the US. and the District of Columbia revealed
that a major reason given by women for late entry into PNC was “I didn’t know I was
pregnant” (CDC, 2000).

It is not exactly clear what directly ‘drives’ this relationship between early
pregnancy recognition and early PNC initiation. On the simplest level, late pregnancy
recogrition would prevent a woman from starting PNC early, simply because a woman
who has not yet acknowledged her pregnancy would be extremely unlikely to seek PNC.
However, early pregrancy recognition does not, by itself, necessitate early initiation of
PNC. What is most likely, though, is that the women who recognize their pregnancy early
are also the ones who welcome their pregrancy and are most concerned to achieve a
positive outcome.

Thus, the concept of “outcome expectations” in SCT (Bandura, 1977) and
“perceived beneﬁts of action” in HPM (Pender et al., 2006) could be used to explain the
reason for the strong relationship between early pregnancy recognition and early PNC.
When pregnant women focus on the ultimate outcome or perceived beneﬁts of early PNC
(e. g., that it will lead to having healthy babies), they are most likely to start PNC early. In
fact, a previous study has shown that at least some adolescents initiate PNC early because

of the “concern over the health of their babies” (T eagle & Brindis, 1998), a ﬁnding that is

112

likely to apply to women of all ages.

The women who initiated PNC early in Daniels et al. (2006) study had positive
attitudes toward pregnancy, were knowledgeable about pregnancy signs and symptoms
and thought PNC was important. It is also possible that the women who recogrized their
pregnancies early and thus initiate PNC early are: those women who had positive
attitudes toward pregnancy and had a good knowledge of pregnancy signs and symptoms,
or who are more aware of their body and body changes.

Parity is another signiﬁcant predictor of early PNC initiation identiﬁed in this
study. Among other, this analysis shows that women with four or more children have a
higher rate of late pregnancy recognition (36.3%) than nullipara (28.8%) and primipara
(24.3%). Earlier studies have also shown that geater maternal parity can be associated
with delayed PNC (Goldani et al., 2004). The current analysis determined in particular
that there are higher odds of early PNC initiation among nulliparas (women with no prior
birth), than among women with one or more prior births. However, women with one prior
birth (primiparas) do not differ from women with no prior birth (nulliparas); it is women
with two or more prior births who are less likely to initiate PNC early. This is not
surprising, since individual experiences, such as prior birth experiences, can inﬂuence
health promoting behaviors (Pender et al., 2006). In particular, women who already had
experience with a pregnancy are less likely to be anxious about the outcome, since they
already know what to expect and what information will be conveyed to them during
PNC. Thus, multiparous women are likely to assign less urgency to receiving PNC
services again, and studies have shown that early initiation of PNC is inﬂuenced by the

importance assigned to receiving PNC (Daniels et al., 2006; Gazrnararian et al., 1999;

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Mikhail, 1999).

By contrast, women with no prior birth may initiate PNC early because they feel
that they do not have sufﬁcient information on how to live healthy during pregnancy, and
to take care of a baby after birth. Therefore, ﬁrst time mothers might be particularly
motivated to initiate PNC early due to their perceived beneﬁts of getting necessary
prenatal teaching and counseling early in pregnancy. In addition, this study has also
shown that women with higher parity tend to have higher rate of late recognition. Late
recognition automatically precludes early PNC. It is also possible for women with higher
parity not to be actively looking for more children and may not easily accept or
acknowledge the existence of a new developing fetus.

The interaction effect of early pregnancy recognition and parity was investigated.
The result showed however that the effect of early pregnancy recognition on early PNC
initiation among nulliparous women is not signiﬁcantly different from its effect among
women with one or more births. In essence, early pregnancy recognition is a strong
predictor of early PNC initiation among all women. It can be concluded then, that
pregnancy recognition is either a very strong motivator to pursue health and initiate PNC
in all women, or it is a marker for women who welcome their pregnancy and are thus
motivated to do everything in their power to assure a good birth outcome. This effect is
visible, even when other personal and environmental factors that could have inﬂuenced
behaviors such as age, marital status, and race/ethnicity have been controlled.

Similar to earlier studies, other signiﬁcant predictors of early PNC irnitiation are
higher levels of education (1 6 years or above), Medicaid coverage and having private

insurance (CDC, 2000; Egerter, et al., 2000; Frisbie, Echevarria, & Hummer, 2001;

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Gazrnararian et al., 1999; Gerstein 2000; Nothnagle, Marchi, Egerter, & Braveman, 2000;
Rosenberg et al., 2006). This is not surprising, since women with just high school
education have been shown to have higher rate of late pregnancy recognition in this
current study. A higher level of education mayprovide better understanding of the
importance of early PNC and maintaining healthy status. Women with higher education
have also been identiﬁed to be more likely to have demonstrated positive health
behaviors in most areas of life (Chandra, Martinez, Mosher, Abma, & Jones, 2005).

The ﬁnding on women’s insurance status suggests that uninsured women
disproportionately start PNC late. Private insurance has stronger effect on early PNC
initiation than Medicaid. Many women on Medicaid get it after pregnancy (Rosenberg et
al., 2006). Among women whose PNC was paid for by Medicaid and state progams,
33% cited lack of insurance coverage as a barrier to early PNC (CDC, 2000). It is
possible that women with no insurance wait till the end of the pregnancy to initiate PNC
when PNC can not be denied. In essence, insurance is still a problem in early PNC
initiation, but Medicaid a bit elevates this. Women on private insurance are most likely to
have had the health insurance before pregnancy. When they become pregnant accessing
PNC might not be a problem, since they have an existing coverage to pay for it. Although
Medicaid provides some leverage for pregnant women when compared to women with no
insurance, the ﬁnding in this study suggests that Medicaid coverage is still not yet
effectively protecting pregnant women from having late PNC as private insurance.
Similar to ﬁndings in other studies, the PRAMS data reveal that the youngest adolescents
have the lowest odds of initiating PNC early (Daniels et al., 2006; Gerstein, 2000;

Gortzak-Uzan, Hallak, Press, Katz, & Shoham-Vardi, 2001; Yu et al., 2001). Although

115

the relationship between maternal age and early PNC initiation is strong, it is not linear.
This means that initially there is a strong effect between increasing age and early PNC
initiation. But when you get to age 26 or more additional effect increases at a slower rate.
Thus, it is the youngest women who are with particularly low odds of early PNC
initiation. A high percentage of pregnancies to adolescents is unintended (Ayoola,
Brewer, & Nettleman, 2006). Therefore, the desire not to be pregnant and a tendency to
deny their pregnancy may mitigate against early PNC among the younger aged women
(Montgomery, 2003).

Marital status, minority race/ethnicity, and history of no previous premature birth
have also been associated with delay in initiation of PNC. Some reasons for these results
have been presented in the literature (Alexander & Slay, 2002; Yu et al., 2001): delay in
PNC initiation among the unmarried women could be because these women tend to have
less social support than married women. Yet women who had the support of the baby’s
father or whose partner was involved in their pregnancy were more likely to get early
PNC (Ingham County Health Department (ICHD), 2004; Martin et al., 2007). This
ﬁnding reﬂects the effect of environmental factors such as interpersonal interactions that
potentially inﬂuence women’s prenatal behavior and time of PNC initiation (Dudgeon &
Inhorn, 2004; Logsdon & Davis, 2003; Schaffer & Lia-Hoagberg, 1997).

The disparity between the non-Hispanic white women and minority women,
namely Black, Asian and Hispanics in terms of early PNC initiation could be due to
various reasons. Mothers’ socio-economic status and ability to pay for PNC as well as
level of education could be factor among the minority women. Although the study

controlled for socio-economic status and mothers’ level of education, it is possible for

116

these variables not to have been connpletely controlled for. This is because the socio-
economic variable is just measuring whether the women were on public assistance or not.
This might not be a complete reﬂection of the mothers’ socio-economic status. The level
of education also shows whether the mothers had more than high school education or not.
This might not differentiate between women who had undergaduate, gaduate and
postdoctoral education. Many of the minority goups are within the low-income goup.
Neighborhood factors and residential segegation have also been associated with health
care access and birth outcomes (Erbaydar, 2003; Farley et al., 2006; Pickett &Pearl,
2001). Therefore residential segegation and thus lower number of available clinics and
densities of obstetrician and gynecologists might occur.

Women with prior adverse birth outcomes tend to obtain earlier care in their
subsequent pregnancies than those who did not experience these events (Elam-Evans et
al., 1997; McDermott, Drews, Adams, Berg, Hill, & McCarthy, 1996). Therefore, it is
possible that if a woman had a positive birth outcome in a prior pregnancy, she might
decide to “relax” and not “bother” about early PNC in subsequent pregnancies since all
went well the ﬁrst time.

Time of Pregnancy Recognition as Predictor of the Number of Prenatal Visits

This study conﬁrms that early pregnancy recognition is associated with a higher
number of PNC visits. The AAP & ACOG (2002) guidelines expect pregnant women to
make 11 to 15 visits for a term pregnancy. On average women in this study made at least
11 PNC visits as expected. Early pregnancy recognition makes it less likely that a
woman will have less than the recommended 11 to 15 visits. Instead, the women who

recognized their pregnancies early had signiﬁcantly higher odds of having more than the

117

11 to 15 visits. This ﬁnding is consistent with the earlier result that women, who
recognize their pregnancies early, also irnitiate care early. In turn, such women are more
likely to make the recommended number of visits and even more.

No study has examined the relationship between the time of pregnancy
recognition and the number of PNC visits. However, a related study focused on the
gestational age at the time of PNC initiation and its effect on the number of PNC visits
(Petrou et al., 2001). Consistent with the current ﬁndings, Petrou and colleagues (2001)
reported that higher gestational age at the time of PNC initiation signiﬁcantly reduced the
number of prenatal visits. When women recognize their pregnancies early and irnitiate
care early, the gestational age at the time of PNC initiation would be low, providing more
time and opportunity for higher numbers of prenatal visits. Studies have shown that
reduced numbers of PNC visits are not necessarily associated with negative birth
outcomes, when compared with average or higher number of PNC visits especially
among low risk women (Carolli et al., 2001; McDufﬁe et al., 1996; Villar et al., 2001).
However, having higher number of visits may provide more opportunities for both
preventive care and health promotion of pregnant women, especially for the high-risk
pregnancies (e. g., multiple births). In the last decade in the U.S., there is an increasing
trend for women with multiple births to seek more than the recommended or average
amount of PNC (Mahler, 1999).

Other factors that appear to contribute towards having less than 11 PNC visits
identiﬁed in this study are: being younger than 16 years; Medicaid coverage or having
private insurance. Many adolescents especially the very young below the age of 16 years

may want to hide their pregnancies or deny its existence due to fear of rejection from

118

their partners, or from their parents for being sexually active (Montgomery, 2003).
Therefore, when adolescents go for PNC, it is likely to be at a high gestational age, which
results in reduced number of PNC visits (Petrou et al., 2001). The protective effect of
Medicaid on having less than the average expected number of PNC visits possibly shows
that efforts to increase access to health for pregnant women through the various Medicaid
expansion progams must have been effective.

Other signiﬁcant predictors of having less than 11 PNC visits are: parity, marital
status, minority race/ethnicity. Women can not irnitiate PNC except if they recognize their
pregnancy. The higher rate of late pregnancy recognition among women with higher
parity (two or more children) in this current study shows that they might also get into
PNC late. Higher rate of late PNC initiation have also been reported among multiparous
and unmarried women (Goldarni et al., 2004; Yu et al., 2001). Or if the multiparous
women recognized their pregnancy and do what they have learnt from prior pregnancies
but without attending all PNC visits, they might also have lesser number of PNC visits. It
is also possible for unmarried women to have reduced number of PNC visits because they
have fewer interpersonal inﬂuences from partners to encourage early PNC irnitiation. In
addition, this study has shown that being in the minority goup namely Black, American
Indian/ Alaskan Native, Asian and Hispanic women is signiﬁcantly associated with lower
odds of initiating PNC early. Correspondingly it is not surprising that they also have
fewer than the recommended numbers of PNC visits.

Pregnancy Recognition and Birth Outcomes
This study examined whether early pregnancy recognition will predict birth

outcomes, namely prematurity, low birth weight (LBW), admission into neonatal

119

intensive care unit (N ICU) and infant mortality, after controlling for the main
confounding variables. The percentages of women who had a premature birth and those
who had LBW babies in this study are less than the national averages (8.9% and 6.9% vs.
12.7% and 8.2% respectively). But the percentages are still higher than the healthy people
2010 goal of 7.6% and 5% respectively (USDHHS, 2000). The lower percentages in this
study may be due to the fact that births below 22 weeks were not considered viable and
were removed from the ﬁnal analysis. In addition, some women who did not have any
PNC were also excluded. Eleven percent of the babies born to women in the study had
NICU admission and less than 1% reported infant mortality.

Early pregnancy recognition is signiﬁcantly associated with lower odds of having
preterm births, LBW babies and NICU admission, after controlling for otlner variables,
even though these associations appear moderate witln odds-ratios usually not deviating
from unity by more than 10%. A causal relationship cannot be drawn between early
pregnancy recognition and the improved birth outcomes among the women studied. But
the SCT and HPM which guides the design of this study postulates human behaviors are
inﬂuenced by the outcome expectations and perceived beneﬁts of actions. Therefore, if
women know that a particular behavior will lead to better outcomes they might decide to
engage in such behaviors.

Adoption of healthy behaviors throughout pregnancy might thus result in better
birth outcomes (Alvik et al., 2006; Ockene et al., 2002; Wong, Perry, Hockenberry,
Lowdennilk, & Wilson, 2006; Zeller, Burke, & Glass, 2006). Studies have consistently
shown that when women recognize their pregnancy they change their behaviors and are

also receptive to learning new things for the welfare of the baby (Alvik et al., 2006; Kost

120

et al., 1998; Ockene et al., 2002; Pirie et al., 2000). Adoption of health-promoting
behavior early in pregnancy such as taking daily multivitamins, stopping or reducing
smoking and drinking, taking balanced meals and avoiding exposure to teratogenic
substances might contribute to the reason why early pregnancy recognition is associated
with having lesser preterm births and LBW babies. Therefore, it is not surprising that
early pregnancy recognition is also associated with reduced NICU admission. Preterm
births and LBW are also associated with various postnatal complications that increase the
risk of admission into NICU (Hamilton et al., 2007; IOM, 2006; Martin et al., 2006;
Marret et al., 2007).

The lack of relationship between the time of pregnancy recognition and infant
mortality is possibly due to the fact that infant mortality is a more general measure of
pregnancy-related mortality. This is because infant death within the ﬁrst 12 months could
have been due to some other causes that were not directly related to the mother’s
pregnancy-related behaviors. For example, sudden infant death syndrome (SIDS), co-
sleeping, shaken baby syndrome, and other forms of child abuse.

Other variables whose effects were controlled for in the analysis in this study are:
time lag, multiple births, parity, marital status, level of education, previous birth
outcomes -LBW and premature birth-, maternal age, maternal race/ethnicity, insurance
status, drinking behavior and smoking behavior.

Time lag and Birth Outcomes

Part of the fourth hypothesis in this study examined the relationship between time

lag and birth outcomes. Many studies are currently discussing whether PNC is effective

in improving birth outcomes. Therefore, the time lag, which is the difference between the

121

time of PNC and the time of pregnancy recognition (PR), was examined (see Figure 2 in
Appendix A). No earlier study has examined PNC from this perspective. On average,
among the early recognizers, there is a longer time lag than among the women who
recognized their pregnancy later. Despite this longer time lag, this study still shows that
women who recognized their pregnancy early tend to initiate PNC early.

There are several plausible reasons for the longer time lag in initiating PNC
among some women who recognized their pregnancies early. First, there are many
studies that have shown that one of the barriers to early PNC is delayed clinic
appointment or inability to get into care early (CDC 2000; Teagle & Brindis, 1998). If the
women were still waiting for their clinic appointment there could be a longer time
between time of pregnancy recognition and time of PNC initiation. Although women who
start PNC later could also have delay in clinic appointment, with the Healthy People 2010
goal, the clinic staffs might see more urgency in getting these late recognizers in as soon
as they contact the clinics. This might tremendously reduce their waiting time compared
to women who tried to initiate care by 6 weeks.

Second, some women upon recognition might want to be sure that truly they were
pregnant or might not want others to know yet, especially women with unintended
pregnancy (Braveman, Marchi, Egerter, Pearl, & Neuhaus, 2000; Peacock et al., 2001;
Sangi-Haghpeykar, et al., 2005). In such situations PNC might not be initiated
immediately even though they had recognized their pregnancy early. Third, at times the
women might not feel that it is important to come for their ﬁrst PNC, especially when
there are no apparent problems, until the pregnancy is a little bit advanced (closer to 10

weeks) and examination of botln the mother and the fetus could be done. [Initiating PNC

122

within 6 weeks might also not be encouraged by the health providers to eliminate non-
viable pregnancies/fetuses. For example, one of the medical manuals suggests that
women should initiate PNC within 6 to 8 weeks (Beers, 2003). Women who recognized
their pregnancy within 4 weeks from their LMP or earlier might not be encouraged to
initiate care immediately. This could create a somewhat longer time lag between
recognition and PNC initiation.

The longer time lag between the time of pregnancy recognition and the time of
PNC initiation is associated with lower odds of having preterm births, LBW babies and
newborn admission into NICU. Longer time lag shows that women delayed their time of
PNC initiation. Earlier ﬁndings in this study show that women who recognized their
pregnancies early tend to have a longer time lag. But this does not mean they did not
initiate PNC early. As postulated by the SCT and the HPM, and as also conceptualized in
this study, human behaviors are inﬂuenced by both the individual’s experiences and other
environmental factors (Bandura, 1986; Pender et al., 2006). In essence, interactions of
women’s perceived health status of being pregnant and some environmental factors could
inﬂuence their actions. These actions include: decisions to adopt the health-promoting
behaviors essential for positive birth outcomes before initiating PNC, and the decision to
eventually initiate PNC.

The environmental factors that could create barriers to accessing PNC such as
delay in getting clinic appointment time could prolong the time when a woman initiates
PNC, even though the woman has recognized her pregnancy (Teagle & Brindis, 1998). In
addition, the woman’s knowledge of the importance of PNC and attitude towards PNC

could inﬂuence her decisions to initiate PNC (Daniels et al., 2006; Mikhail, 1999).

123

Therefore, it is possible for a woman to recognize her pregnancy and decides to change
all the behaviors that she thinks could negatively impact the fetus before initiating PNC.
Adoption of healthy behaviors during the early stage of organogenesis despite non-entry
into PNC and thus longer timelag might contribute to having positive birth outcomes.

The ﬁfth hypothesis concerning the interaction of early pregnancy recognition and
being a nullipara could not be conﬁrmed. This suggests that early pregnancy recognition
has same impact on all women. It is worth noting however, that the odds ratio for infant
mortality was less than 1, even though the interaction effect between parity and early
pregnancy recognition did not reach statistical signiﬁcance. This suggests that early
pregnancy recognition is possibly the strong factor that inﬂuences birth outcomes,
irrespective of the mother’s parity.

Limitations of the Study

This study provides very important explanations of the relationship between time
of pregnancy recognition, PNC use and birth outcomes among women of childbearing
age in PRAMS population. However, the study is not without some limitations that
should be taken into consideration while interpreting the results.

The PRAMS data used for this study refers to the population of women who gave
birth within 29 states in United States; this somewhat limits the generalizability of the
study. Even though these data is on estimated 5.5 million women it is about 48% of the
estimated population of women who have had a child in a year in the US (US. Census
Bureau, 2005).

PRAMS data is based on self-report, and some of the key variables namely the

time of pregnancy recognition and the time of PNC initiation are subject to potential

124

recall bias. Altlnough to reduce the problem of recall bias, the data are collected within 2
to 6 months of birth. Another possible problem is the tendency to want to give socially
acceptable answers, therefore, it is possible that some women claim they irnitiated PNC at
an earlier time than they did. With the questions on smoking and drinking behavior
before during pregnancy, it is also possible for some women not to have indicated that
they drank or smoked during pregnancy. All these might cause overestimation of the
effect of the key variables. But considering that the PRAMS population is among women
with live birth, the effect of pregnancy recognition in birth outcomes could have been
underestimated. This is because, women with fetal deaths and still births have not been
included in the PRAMS survey.

The measure of the time of pregnancy recognition in this study focused on the
time that women were sure of their pregnancy. The PRAMS question asked women to
state the time that the pregnancy was conﬁrmed at a clirnic or by a doctor. But it is
possible for some women to have been sure of their pregnancy earlier than the time that it
was conﬁrmed at a clinic or by a doctor. Some women could have even been sure based
on signs and symptoms or home pregnancy tests. This might create some ambiguity in
the way that women answered the question.

A simple measure of income in terrnns of being on other public assistance was used
in this study. This measure did not take into account the whole range of income found
within the population and does not present a sufﬁciently detailed picture of the income
distribution in the population.

The measure for the time of PNC initiation is also based on women’s self-report

of when they initiated PNC. Some women stated the same date for the time of pregnancy

125

recognition and the time they initiated PNC. So some women might not be able to 2
separate the time they had a pregnancy test from the time they actually initiated PNC.
The use of birth certiﬁcates in this study is also another form of limitation because the
reliability of the birth certiﬁcate has been questioned by various authors (DiGiuseppe et
al., 2002; Dobie et al., 1998; Northam & Knapp, 2006). Although the birth certiﬁcate is
not a “gold standard” efforts have been directed at improving its reliability and there is
hardly any human activity that is free of errors.

Finally, this study did not examine the concept of urnintended pregnancy, which
could be a predictor of delayed recognition. This study also did not examine the process
of pregnancy recognition, which include conﬁrmation (this study’s focus), acceptance,
decision, and action (which could be to initiate PNC) (Peacock et al., 2001).

Nursing Implications

Future Nursing Research

This is the ﬁrst study to examine the relationship between pregnancy recognition
and birth outcomes. The strong positive effect of early pregnancy recognition on PNC
initiation and moderate effect on birth outcomes, namely prematurity, LBW and NICU
admission conﬁrmed in this study provide evidence upon which to base future nursing
research and interventions on pregnancy recognition.

Pregnancy recognition is an evolving concept and has been conceptualized from
three main perspectives (physiological, psychosocial and conﬁrmatory). It is important
for future studies to examine the process of pregnancy recognition and the inﬂuence of
the process of pregnancy recognition on the time of PNC initiation. It is possible that the

different phases in the process of recognition would inﬂuence women’s behavior. Future

126

studies should also identify the stage in the process of pregnancy recognition at which
behavior change occurs. Future research may also consider a trend analysis regarding the
time of pregnancy recognition in the PRAMS population.

Pregnancy recognition has been examined in this study as a predictor of birth
outcomes, but it is also necessary to examine those characteristics that could predict early
pregnancy recognition among women of childbearing age. For example, women with
unintended pregnancies have been identiﬁed to be at increased risk of delayed pregnancy
recognition (Kost et al., 1998). It will be relevant to examine the percentages of early
recognizers who had unintended pregnancy and whether this was associated with their
time of PNC initiation.

There is a need for a population-based study that would examine whether good
knowledge of pregnancy signs and symptoms or being aware of ones’ body and body
changes signiﬁcantly predict early pregnancy recognition. It will also be necessary to
know which goup of women (e. g., women with pre-existing, medical conditions such as
hypertension, diabetes, multiple births etc.) beneﬁts most ﬁ'orn early pregnancy
recognition.

Although early pregnancy recognition is a strong predictor of early PNC, some
women still had a longer time lag between the time of pregnancy recognition and the time
of PNC initiation. Studies have discussed different reasons for delay in PNC irnitiation
among women generally (Bennett et al., 2006; CDC, 2000; Gazrnararian et al., 1999;
Rosenberg et al., 2006). These studies did not specify whether these women were early
recognizers or not. It is important to investigate whether there are any other factors that

will explain why some women who recognized their pregnancies before 6 weeks would

127

not initiate PNC immediately.

No causal relationship can be drawn between early pregnancy recognition and
birth outcomes. Future studies should examine the moderating and mediating effect of
health promoting behaviors such as not smoking, not drinking and taking vitamins among
early pregnancy recognizers on birth outcomes.

The HPM postulates that perceived beneﬁts of action inﬂuences the health
promoting behavior. Studies have shown that early initiation of PNC is inﬂuenced by the
importance assigned to receiving PNC (Daniels et al., 2006; Gazrnararian et al., 1999;
Mikhail, 1999). Nulliparas (women with no prior birth) in this study have higher odds of
initiating PNC early than women with one or more prior birtlns. Based on the concept of
perceived beneﬁts of action, if women with prior births had good pregnancy outcomes
with the prior pregnancy, this might inﬂuence their perception of their need for PNC in
subsequent pregnancies and the level of importance assigned to receiving PNC services
again. It is therefore timely to examine whether multiparous women are more likely to
assign less importance to receiving PNC services and the effect of this on the time of
PNC initiation. This study has also shown that early recognition is associated with higher
number of PNC visits. It is important to know which goup of people beneﬁts most ﬁom
higher numbers of PNC visits. In addition, future studies should examine the relationship
between average or higher number of PNC visits and birth outcomes.

Having a,medical high risk condition is not one of the factors examined in this
study. It will be relevant for ﬁrture investigations on the predictive effect of time of
pregnancy recognition on birth outcomes to also consider the inﬂuence of maternal pre-

existing medical conditions such as diabetes and hypertensive disorders.

128

Nursing practice

Nursing is in a unique position to promote optimal level of wellness among
women at different stages through their reproductive lifespan. Nurses are available at all
the health care settings where a woman of childbearing age is likely to receive care.
These settings include the acute care setting, outpatient department, family planning
clinic, child welfare clinic and the PNC clinic.

The ﬁndings of this study have implications for the roles of nurses, nnidwives and
other advanced practice nurses in promoting healthy behaviors among women of
childbearing age during the preconceptual and interconceptional period. There are some
factors that are identiﬁed in this study that can not be changed (e.g., maternal age, parity
and race/ethnicity). These non-modiﬁable factors can be used by nurses to identify some
women at higher risk of delayed pregnancy recognition and the subsequent early PNC
initiation. It is also important to focus on the modiﬁable behaviors that women might be
able to change through the assistance of nurses.

Early pregnancy recognition affords women the opportunity to adopt health-
promoting behaviors (Kost et al., 1998; Lumley, Watson, Watson, & Bower, 2005)
during the early stage of organogenesis. Early pregnancy recognition also provides an
avenue for women, especially those at risk of adverse outcomes, to adopt health-
promoting behaviors, even before initiating PNC. Women can only adopt the healthy
behaviors if they are aware of the importance of it. Association of early pregnancy
recognition with early PNC and reduced premature births, LBW and NICU admission
provides a rationale for nurses to encourage early pregnancy recognition and to continue

to encourage healthy behaviors among women of childbearing age.

129

Nursing focused activities that could be done as part of preconceptual health and

counseling, include increasing women’s awareness of importance of early pregnancy

recognition. This can be achieved by:

l.

Incorporating teachings on early signs and symptoms into nursing care at the
different health care settings.

Nurses, midwives and other advanced practice nurses can also provide
information about fetal development during the early stage of pregnancy and how
mothers’ preconceptual and prenatal behaviors can inﬂuence the process of fetal
development. This information can be provided through active teaching sessions
during hospital or clinic visit, or during home-based visits by commmnity heath
nurses. Nurses can also facilitate distribution of educational brochures or video
presentation of facts on early fetal development for women during clirnic visits for

annual examinations or other primary care visits.

. Nursing interventions can be designed to focus on people at higher risk of late

recognition and late PNC initiation such as unmarried women and women with
higher parity. Part of the educational emphasis on the importance of early
pregnancy recognition on fetal development could be directed at tlnese goups of
women even before they got pregnant.

Nurses and other health providers could also educate older women of childbearing
age of the risk of pregnancy even at older age, and the need to be vigilant about
recognizing their pregnancy promptly as long as they could still have children.
Nurses can also be involved in initiatives to promote pregnancy screening among

women at higher risk of having late pregnancy recognition such as unmarried

130

women, women with higher parity and unintended pregnancy.

. Nurses can also ensure that all women of childbearing age are screened for
pregnancy before diagnostic procedures that could expose them to teratogenic
substances.

Nurses can also provide information for women of childbearing age on the'list of
some medications that are contraindicated during pregnancy. Women who are on
such medications can be encouraged to use very effective contraception such as
Depo provera or intrauterine contraceptive devices (IUCD) or keep home
pregnancy test on hand and test of pregnancy in case they have unprotected
intercourse.

. Home pregnancy testing is a developing technology that has been found to geatly
increase women’s opportunity to recognize pregnancy early (Morroni & Moodley,
2006). Nurses and other health care professionals will also need to provide basic
information on the use of home pregnancy testing to women during hospital,
home or clinic visits. Provision of information should not be limited to just one
aspect of nursing care (e.g., family planning). Information would have to be made
available during routine hospital or clinic visits that bring women of childbearing

age in contact with the health care system.

Policy and Public Health Implications

The Institute of Medicine (IOM) developed six aims to improve quality of care

with the goal of improving health outcomes in United States. Important quality

shortcomings of health care delivery that the Institute of Medicine report “Crossing the

quality Chasm: A New Health System for the let Century” expects to be addressed

131

include the provision of effective, patient-centered, and timely care (IOM, 2001). Late
pregnancy recognition precludes early PNC and the opportunity to receive effective and
timely care. If the women (over 90%) who recognized their pregnancy by twelve weeks
in this study could get into care immediately, early pregnancy recognition could
contribute to the achievement of the Healthy People 2010 goal of 90% of women in US.
entering PNC in the ﬁrst trimester.

There are currently debates about the effectiveness of PNC to reduce birth
outcomes (Alexander & Kotelchuck, 2001). In this study a longer time lag between time
of pregnancy recognition and time of PNC initiation is not associated with poor
outcomes. This shows that the timelag might not really be the issue, but rather the PNC.
With the advent of promotions on preconceptual health, it is possible that most of the
problems related to poor outcomes are related to maternal preconceptual and prenatal
behaviors. Early recognition is a strong behavioral stimulus that encourages women to
change their behaviors (Alvik et al., 2006; Kost et al., 1998; Ockene et al., 2002; Pirie et
al., 2000). Therefore, if women could be motivated to recognize their pregnancies early
and change their behaviors, there might be improved birth outcomes.

The percentage of women who did not initiate PNC was relatively small. But late
and no PNC have been associated with poor birth outcomes. Therefore, a population-
based intervention could be designed to reach this goup of women through the mass
media. Educational campaigns on the effect of some risky behaviors in the early
pregnancy period on fetal development could be designed for the public. This will be to
inform all women and others in their environment that could positively inﬂuence the

women’s behaviors. Reaching out to the public sphere provides a geat opportunity to

132

also reach the women without access to PNC or with delayed access to PNC.

Although the causes of preterm delivery are not fully understood (Hamilton et al.,
2007; Moore, 2003), the association between early pregnancy recognition and reduction
in preterm births produces a new perspective to address some behavioral factors that
could be associated with preterm births. One of the advantages of the use of SCT as a
conceptual ﬁamework is that it leads one to think of the opportunities for the
manipulation of the environment in order to inﬂuence behaviors (Baranowski et al.,
2002). Interventions could be designed at a population-based level to make the
environment conducive for early pregnancy recognition. For example, the creation of the
non-smoking environment creates an environment that discourages smoking. Some things
that could be done at the population based level to inﬂuence the environment of
childbearing age women and sensitize them towards early pregnancy recognition include:

0 Distribution of free pregnancy test kit to women at risk of delayed pregnancy
recognition. This might be able to increase the population of women who
recognize their pregnancies early.

0 Encouraging women of childbearing age especially those at risk of delayed
pregnancy recognition to always keep a pregnancy test kit on hand as part of the
health promoting behaviors.

0 Education of high school students on the importance of pregnancy recognition.

0 Distribution of educational materials on the importance of early pregnancy
recognition in hospitals and clinics.

Conclusion

This study provides baseline information on the relationship between early

133

pregnancy recognition and main birth outcomes namely prematurity, LBW, and NICU
admission. This study is unique in that it is based on a large data set that provides a form
of statistical “robustness” and stability. In addition, a combination of ﬁve years of data
provides a stable data set on pregnancy recognition. Timing of pregnancy recognition is a
modiﬁable behavior that is a strong predictor of PNC use and the amount of exposure to
PNC in terms of the number of prenatal visits among women of childbearing age. Over
72% of women in the PRAMS population studied recognized tlneir pregnancy within six
weeks of conception, and 90% have recognized their pregnancies by twelve weeks. Early
pregnancy recognition is also a moderate predictor of reduced premature births, LBW
and NICU admissions.

Although the exact cause of the reduction in adverse outcomes is not presently
understood, research shows that once a woman recognizes that she is pregnant, she is
likely to change her behaviors that might adversely affect a fetus. Many of these adverse
behaviors cause geat harm during the earliest weeks of pregnancy, sometimes before a
woman realizes she is pregnant. Therefore early pregnancy recognition provides
opportunities for women to reconsider their behaviors early in pregnancy before
permanent harm is done to the developing fetus. The SCT and HPM also provide
explanation for change in human behaviors, which guides in better understanding of why
women could change their behavior upon pregnancy recognition.

Many ﬁndings in this study have strong implications for the educational role of
the nurse and other health providers in order to reduce negative birth outcomes. This
study provides a rationale for early pregnancy interventions to promote healthy behaviors

among women. This study will also add credence to the studies and interventions on

134

promoting preconceptual healtln for women of childbearing age. Speciﬁc emphasis could
be placed on promoting early pregnancy recognition among women that are at high risk
for delayed pregnancy recognition. Future studies need to examine pregnancy recognition
as an outcome to gain a deeper understanding of the antecedent factors in the process of
pregnancy recognition among women of childbearing age. Promotion of early pregnancy
recognition by nurses and all the health care providers may provide a wonderful means of
empowering women to have a better understanding of their body and to be active

participants in their health care and that of their unborn child.

135

APPENDICES

136

Appendix A- Relationship between time lag, pregnancy recognition and time of prenatal

care initiation.

C PR PNC

Time lag

Figure 2: Relationship between time lag, pregnancy recognition and time of prenatal care

initiation.

Key: C —Time of Conception

PR — Time of pregnancy recognition

PNC- Time of PNC initiation

137

Appendix B- State Distribution in the Analysis Sample

Table B

State Distribution in the Analysis Sample

STATES
Alabama
Alaska
Arkansas
Colorado
Florida
Hawaii
Illinois
Louisiana
Maryland
Maine
Michigan
Minnesota
Mississippi
Montana
North Carolina
North Dakota
Nebraska
New Jersey
New Mexico
New York
Ohio
Oklahoma
Oregon
Rhode Island
South Carolina
Utah
Vermont
Washington
West Virginia
Total

Note: The statistics does not include women with fetal deaths and still births

Analysis sample (%)
0.57
3.78
2.22
4.33
13.06
1.09
11.33
4.08
3.11
0.89
5.19
1.70
0.67
0.18
7.60
0.12
1.67
2.67
1.63
7.79
9.65
3.06
0.69
0.37
3.32
3.14
0.35
4.54
1.17

100

138

Appendix C — PRAMS Questionnaire

Pregnancy Risk Assessment Monitoring System (PRAMS)

Phase 4 Core Questionnaire

139

First, we would like to ask a few questions about you and the time before you became

pregnant with your new baby. Please check the box next to your answer.

1. Just before you got pregnant, did you have health insurance? (Do not count Medicaid.)

No

Yes

2. Just before you got pregnant, were you on Medicaid?

No

Yes

3. In the month before you got pregnant with your new baby, how many times a week did you take a
multivitamin (a pill that contains many different vitamins and minerals)?

I didn’t take a multivitamin at all

1 to 3 times a week

4 to 6 times a week

Every day of the week

4. What is your date of birth?

[BOX] [BOX] [BOX]

Month Day Year

5. Just before you got pregnant, how much did you weigh?

Pounds OR Kilos

6. How tall are you without shoes?

[BOX] Feet [BOX] Inches
OR [BOX] Centimeters

Insertion mint for Standard guestignm L10-Lll

7. Before your new baby, did you ever have any other babies who were born alive?

No a Go to Question 10
Yes

8. Did the baby born just before your new one weigh 5 pounds, 8 ounces (2.5 kilos) or less at birth?

No
Yes

140

9. Was the baby just before your new one born more than 3 weeks before its due date?

No
Yes

Insertion point for Standard Questiongs] P7-P8

10. Thinking back to just before you got pregnant, how did you feel about becoming pregnant?

I wanted to be pregnant sooner

I wanted to be pregnant later

I wanted to be pregnant then

I didn’t want to be pregnant then or at any time in the future

Insertion mint for Standard Questions] 95

11. When you got pregnant with your new baby, were you trying to become pregnant?

No
Yes 2 Go to Question 14

12. When you got pregnant with your new baby, were you or your husband or partner doing
anything to keep from getting pregnant? (Some things people do to keep from getting
pregnant include not having sex at certain times [rhythm], and using birtln control methods
such as the pill, Norplant®, shots [Depo-Provera®], condoms, diaphragm, foam, IUD, having
their tubes tied, or their partrner having a vasectomy.)

No
Yes 2 Go to Question 14

13. What were your or your husband’s or partner’s reasons for not doing anything to keep from
getting pregnant?

I didn’t mind if I got pregnant

I thought I could not get pregnant at that time

I bad side effects from the birth control method I was using

I had problems getting birth control when I needed it

I thought my husband or partrner or I was sterile (could not get pregnant at all)
My husband or partner didn’t want to use anything

Other E Please tell us:

[BOX]

Insertion point for Standard Questionm E3
Insertion ﬂint for Standard guestignm A1-A3

141

The next questions are about the prenatal care you received during your most recent
pregnancy. Prenatal care includes visits to a doctor, nurse, or other health care worker
before your baby was born to get checkups and advice about pregnancy. (It may help to
look at a calendar when you answer these questions.)

14. How many weeks or months pregnant were you when you were sure you were pregnant? (For
example, you had a pregnancy test or a doctor or nurse said you were pregnant.)

[BOX] Weeks OR [BOX] Months

I don’t remember

15. How many weeks or months pregnant were you when you had your ﬁrst visit for prenatal care?
(Don’t count a visit that was only for a pregnancy test or only for WIC [the Special
Supplemental Nunition Program for Women, Infants, and Children].)

[BOX] Weeks OR [BOX] Montlns

I didn’t go for prenatal care

16. Did you get prenatal care as early in your pregnancy as you wanted?

No
Yes Go to Question 18
I didn’t want prenatal care Go to Question 18

17. Did any of these things keep you from getting prenatal care as early as you wanted?

I couldn’t get an appointment earlier in my pregnancy

I didn’t have enough money or insurance to pay for my visits
I didn’t know that I was pregnant

I had no way to get to the clinic or doctor’s ofﬁce

The doctor or my health plan would not start care earlier

I didn’t have my Medicaid card

I had no one to take care of my children

I had too many other things going on

Other =5 Please tell us:

[BOX]

If you did not go for prenatal care, go to Page 4, Question 21.

142

18. Where did you go most of the time for your prenatal visits? (Do not include visits for WIC.)

Hospital clirnic
Health department clinic
Private doctor’s ofﬁce or HMO clinic

Other 2 Please tell us:
[BOX]

19. How was your prenatal care paid for?

Medicaid
Personal income (cash, check, or credit card)
Health insurance or HMO

Other 5 Please tell us:
[BOX]

20. During any of your prenatal care visits, did a doctor, nurse, or other health care worker talk
with you about any of the things listed below? (Please count only discussions, not reading
materials or videos.) For each item, circle Y (Yes) if someone talked with you about it or
circle N (No) if no one talked with you about it.

N o
a. How smoking during pregnancy could affect your baby .............................................................. N
b. Breastfeeding your baby ............................................................................................................... N
c. How drinking alcohol during pregnancy could affect your baby ................................................. N
(1. Using a seat belt during your pregnancy ...................................................................................... N
e. Birth control methods to use after your pregnancy ....................................................................... N
f. Medicines that are safe to take durirng your pregnancy ................................................................ N
g. How using illegal drugs could affect your baby ........................................................................... N
h. Doing tests to screen for birth defects or diseases that run in your family ................................... N
i. What to do if your labor starts early ............................................................................................. N
j. Getting your blood tested for HIV (the virus that causes AIDS) .................................................. N
k. Physical abuse to women by their husbands or partners ............................................................... N

Insertion mm’ t for Standard guestion]s] Rl-RS
Insertion point for Stmdard Questionm R9-Rll
Insertion mint for Standard guestion]s] R6-R8
Insertion point for Standard guestion]s] Il-I4
Insertion point for Standard guestion]s] Gl-G4
Insertion point for Standard guestion]s] L12-L15

143

~<~<~<r<r<r<~<<r<r<~<§

The next questions are about your most recent pregnancy and things that might have
happened during your pregnancy.

21. During your pregnancy, were you on WIC (the Special Supplemental Nutrition Program for
Women, Infants, and Children)?

No
Yes

22. Did you have any of these problems during your pregnancy? For each item, circle Y (Yes) if you
had the problem or circle N (N o) if you did not.

No Yes

a. Labor pains more than 3 weeks before your baby was due (preterm or early labor) .................... N Y
b. High blood pressure (including preeclampsia or toxemia) or retained water (edema) ................. N Y
c. Vaginal bleeding ........................................................................................................................... N Y
(1. Problems with the placenta (such as abruptio placentae, placenta previa) ................................... N Y
e. Severe nausea, vonniting, or dehydration ...................................................................................... N Y
f. High blood sugar (diabetes) .......................................................................................................... N Y
g. Kidney or bladder (urinary tract) infection ................................................................................... N Y
h. Water broke more than 3 weeks before your baby was due (premature rupture of

membranes, PROM) ...................................................................................................... N Y
i. Cervix had to be sewn shut (incompetent cervix, cerclage) ......................................................... N Y
j. You were hurt in a car accident .................................................................................................... N Y

I If you did not have any of these problems, go to Question 24.

23. Did you do any of the following things because of these problem(s)?

I went to the hospital or emergency room and stayed less than 1 day

I went to the hospital and stayed 1 to 7 days

I went to the hospital and stayed more than 7 days

I stayed in bed at home more than 2 days because of my doctor’s or nurse’s advice

Insertion point for Standard guestion]s] Nl-N4
Insertion mint for Standard guestion]s] L4-L7

The next questions are about smoking cigarettes and drinking alcohol.
24. Have you smoked at least 100 cigarettes in the past 2 years? (A pack has 20 cigarettes.)

No 5 Go to Question 28
Yes

144

25. In the 3 months before you got pregnant, how many cigarettes or packs of cigarettes did you
smoke on an average day? (A pack has 20 cigarettes.)

[BOX] Cigarettes OR [BOX] Packs

Less than 1 cigarette a day
I didn’t smoke
I don’t know

26. In the last 3 months of your pregnancy, how many cigarettes or packs of cigarettes did you smoke
on an average day?

[BOX] Cigarettes OR [BOX] Packs

Less than 1 cigarette a day
I didn’t smoke
I don’t know

27. How many cigarettes or packs of cigarettes do you smoke on an average day now?
[BOX] Cigarettes OR [BOX] Packs

Less than 1 cigarette a day

.I don’t smoke
I don’t know

Insertion mint for Standard guestion(s] Ul-U2

28. Have you had any alcoholic drinks in the past 2 years? (A drink is 1 glass of wine, wine cooler, can
or bottle of beer, shot of liquor, or mixed drink.)

No -:- Go to Question 31
Yes

29. a. During the 3 months before you got pregnant, how many alcoholic drinks did you have in an
average week?

Ididn’tdrink then

Less than 1 drink a week
1 to 3 drinks a week

4 to 6 drinks a week

7 to 13 drinks a week

14 drinks or more a week
Idon’t know

b. During the 3 months before you got pregnant, how many times did you drink 5
alcoholic drinks or more in one sitting?

[BOX] Times

I didn’t drink then

145

I don’t know

30. a. During the last 3 months of your pregnancy, how many alcoholic drinks did you have in an
average week?

I didn’t drink then

Less than 1 drink a week
1 to 3 drinks a week

4 to 6 drinks a week

7 to 13 drinks a week

14 drinks or more a week
I don’t know

b. During the last 3 months of your pregnancy, how many times did you drink 5
alcoholic drinks or more in one sitting?

[BOX] Times
I didn’t drink then
I don’t know

Pregnancy can be a difﬁcult time for some women. These next questions are about things
that may have happened before and during your most recent pregnancy.

31. This question is about things that may have happened during the 12 months before your new
baby was born. For each item, circle Y (Yes) if it happened to you or circle N (No) if it
did not. (It may help to use the calendar.)

No Yes
a. A close family member was very sick and had to go into the hospital ......................................... N Y
b. You got separated or divorced from your husband or partner ...................................................... N Y
c. You moved to a new address ........................................................................................................ N Y
(I. You were homeless ....................................................................................................................... N Y
e. Your husband or partner lost his job ............................................................................................ N Y
f. You lost your job even though you wanted to go on working ...................................................... N Y
g. You argued with your husband or partner more than usual .......................................................... N Y
h. Your husband or partner said he didn’t want you to be pregnant ................................................. N Y
i. You had a lot of bills you couldn’t pay ........................................................................................ N Y
j. You were in a physical ﬁght ......................................................................................................... N Y
1c You or your husband or partner went to jail ................................................................................. N Y
1. Someone very close to you had a bad problem with drinking or drugs ........................................ N Y
m. Someone very close to you died ................................................................................................... N Y

32. a. During the 12 months before you got pregnant, did your husband or partner push, hit, slap,
kick, choke, or physically hurt you in any other way?

No
Yes
b. During the I 2 months before you got pregnant, did anyone else physically hurt you in
any way?
No

146

Yes
33. a. During your most recent pregnancy, did your husband or partner push, hit, slap, kick, choke,
or physically hurt you in any other way?

No
Yes

b. During your most recent pregnancy, did anyone else physically hurt you in any way?

No
Yes

Insertion point for Standard guestion[s) M1

The next questions are about your labor and delivery. (It may help to look at the calendar
when you answer these questions.)

Insertion point for Standard guestion[s[ Kl—K4

34. When was your baby due?

[BOX] [BOX] [BOX]

Month Day Year

35. When did you go into the hospital to have your baby?

[BOX] [BOX] [BOX]
Month Day Year

I didn’t have my baby in a hospital

36. When was your baby born?

[BOX] [BOX] [BOX]

Month Day Year

37. When were you discharged from the hospital after your baby was born? (It may help to use the
calendar.)

[BOX] [BOX] [BOX]
Month Day Year

I didn’t have my baby in a hospital

147

38. After your baby was born, was he or she put in an intensive care unit?
No

Yes
I don’t know

39. After your baby was born, how long did he or she stay in the hospital?
Less than 24 hours (Less than 1 day)

24—48 hours (1—2 days)

3 days

4 days

5 days

6 days or more

My baby was not born in a hospital
My baby is still in the hospital

40. How was your delivery paid for?

Medicaid
Personal income (cash, check, or credit card)
Health insurance or HMO

Other 5 Please tell us:

[BOX]

The next questions are about the time since your new baby was born.
41. What is today’s date?

[BOX] [BOX] [BOX]

Month Day Year

42. Is your baby alive now?

No

Yes a Go to Question 44

43. When did your baby die?

[BOX] [BOX] [BOX]
Month Day Year

Go to Page 11, Question 56

44. Is your baby living with you now?

No a Go to Page 11, Question 56

148

Yes

45. Did you ever breastfeed or pump breast milk to feed your new baby after delivery?

No 5 Go to Question 49
Yes

Insertion mint for Standard guestion[s) B1

46. Are you still breastfeeding or feeding pumped milk to your new baby?

No

Yes a Go to Question 48

47. How many weeks or months did you breastfeed or pump milk to feed your baby?
[BOX] Weeks OR [BOX] Months

Less than 1 week

Insertion point for Standard guestion[s[ B2

48. How old was your baby the ﬁrst time you fed him or her anything besides breast milk? (Include
formula, baby food, juice, cow’s milk, water, sugar water, or anything else you fed your
baby.)

[BOX] Weeks OR [BOX] Months

My baby was less than one week old
I have not fed my baby anything besides breast milk

If your baby is still in the hospital, go to Page 11, Question 56.

49. About how many hours a day, on average, is your new baby in the same room with someone who
is smoking?

[BOX] Hours
Less than one hour a day
My baby is never in the same room with someone who is smoking

50. How do you rnost often lay your baby down to sleep now?

On his or her side
On his or her back

149

On his or her stomach

Insertion point for Standard guestion(s) F1

51. Was your baby seen by a doctor, nurse, or other health care provider in the ﬁrst week after he or
she left the hospital?

No a Go to Question 53
Yes
52. Was your new baby seen at home or at a health care facility?

At home
At a doctor’s office, clinic, or other health care facility

53. Has your baby had a well-baby checkup?

No a Go to Question 56

Yes

54. How many times has your baby been to a doctor or nurse for a well-baby checkup? (It may help

to use the calendar.)

[BOX] Times
55. Where do you usually take your baby for well-baby checkups?

Hospital clinic
Health department clinic
Private doctor’s ofﬁce or HMO clinic

Other :- Please tell us:

[BOX]

Insertion mint for Standard guestion[s) H5
Insertion mint for Standard guestion[s) Tl-T3
Insertion mint for Standard guestion[s) Xl-X3
Insertion point for Standard guestion(s[ X5
Insertion point for Standard guestion(s[ Hl-H4

150

The next few questions are about the time after you gave birth to your new baby and things
that may have happened after delivery.

56. Are you or your husband or partner doing anything now to keep from getting pregnant? (Some
things people do to keep from getting pregnant include having their tubes tied or their partner
having a vasectomy, using birth control methods like the pill, Norplant®, shots [Depo-
Provera®]. condoms, diaphragm, foam, IUD, and not having sex at certain times [rhythm].)

No
Yes a Go to Question 58

57. What are your or your husband’s or partner’s reasons for not doing anything to keep from
getting pregnant now?

I am not having sex

I want to get pregnant

I don’t want to use birth control

My husband or partner doesn’t want to use anything
I don’t think I can get pregnant (sterile)

I can’t pay for birth control

I am pregnant now

Other 5 Please tell us:

[BOX]

Insertion mint for Standard guestion[s) El
Insertion point for Standard guestion]s[ E2
Insertion point for Standard guestion[s) L8-L9
Insertion mint for Standard guestion[s[ M2-M3
Insertion point for Standard guestion]s[ 01-03

The next questions are about your family and the place where you live.

58. Which rooms are in the house, apartment, or trailer where you live?

Living room

Separate dining room

Kitchen

Bathroom(s)

Recreation room, den, or family room
Finished basement

Bedrooms 2 How many? [BOX]

151

59. Counting yourself, how many people live in your house, apartment, or trailer?
[BOX] Adults (people aged 18 years or older)

[BOX] Babies, children, or teenagers (people aged 17 years or younger)

Insertion mint for Standard guestiongs) P17P6
Insertion point for Standard guestion]s) P9-P10

60. What were the sources of your household’s income during the past 12 months?

Paycheck or money from a job

Aid such as Temporary Assistance for Needy Families (TANF), welfare, public assistance, general
assistance, food stamps, or Supplemental Security Income

Unemployment beneﬁts

Child support or alimony

Social security, workers’ compensation, veteran beneﬁts, or pensions

Money from a business, fees, dividends, or rental income

Money from family or friends

Other 5 Please tell us:

[BOX]

Insertion point for Standard guestion[s) J1

152

Please use this space for any additional comments you would like to make about the health of
mothers and babies in

 

Thanks for answering our questions!

153

Your answers will help us work to make mothers and babies healthier.

154

Appendix D- Deﬁnition of Terms

The following are the explanations of some of the terms used in this study:
Pregnancy recognition:
A one-time experience when a woman was sure that she was pregnant
Early pregnancy recognition:
The woman was sure of the existence of the pregnancy by 6 weeks of pregnancy or
gestation.
Delayed or late pregnancy recognition:
The woman was sure of the existence of the pregnancy after 6 weeks (6.1 weeks and
above)
Preconceptual health:
Health care received by a woman of childbearing age before conception
Periconceptional period:
One to three months before conception through 12 weeks gestation
Interconceptional period:
The periods between a woman’s two pregnancies
First trimester:
The ﬁrst 12 weeks of pregnancy
Early PNC initiation:
The initiation of PNC within the ﬁrst trimester (12 weeks) of pregnancy
Participation in PN C:
Had at least one PNC visit irrespective of the time of initiation.

Adequate PNC:

155

Initiation of PNC within the ﬁrst trimester and adherence to appropriate number of PNC
visits expected for the duration of the pregnancy.

Prematurity:

The birth of a baby that occurs at a gestational age below 37 weeks
Low birth weight (LB ”0:

Babies that have a weight below 2500 grams at birth

Neonatal death:

Death of babies within the ﬁrst 28 days of life

Infant Mortality:

Death of a baby between birth and under one year of age
Primigravida:

Women pregnant for the ﬁrst time

Multigravida:

Women with at least one prior pregnancy

Nullipara:

Women with no prior birth.

Primiparas:

Women with one prior birth

Multipara

Women with two or more prior births

156

 

@Litrt
+ an:
WITH?

Human Research
Protection Programs

 

COMMUNITY RESEARCH
INSTITUTIONAL REVIEW
BOARD (CRIRB)

SOCIAL SCIEIDEI
BEHAVDRALI EDUCATION
INSTITUTIONAL REV“
BOARD [SIRE]

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Fax: 5174324503

wwwhunenresearchmsuedu
lFIBOrreuedu

 

MSU ll arr glimmer-ection
equal-opportunity institution.

MICHIGAN STATE Revision
Approval

October 18. 2007

To: Manfred STOMMEL
8222 West Fee Hall
MSU

Re: lRBli X06-671 Category. EXEMPT 1-4
Revision Approval Date: October 18. 2007
Project Expiration Date: August 8. 2009

Title: ‘Timing of pregnancy recognition as a predctor of prenatal care Initiation and birth outcomes.“

The Institutional Review Board has completed their review of your project I am pleased to advise you that the
revision has been approved.

This letter notes approval of the new title.

The review by the committee has Iound that your revision Is condstent with the continued protection of the rights
and welfare of human sub]ects. and meets the requirements of MSU's Federal Wide Assurance and the Federal

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between the iRB and the investigators. We look toward to working with you as we both fulfill our responsibilities.

Renewals: iRB approval is valid until the expiration date Isted above. It you are continuing your project, you
mustsubrnlt anAppllcatlon forRenewelappIIcation at leastone month betereexplration. Ifthe project is
completed. please submit an Applicadon for Permanent Closure.

Revisions: The IRB must review any changes In the project. prior to initiation of the change. Please submit an
Application forRevision to have your changes reviewed. It changes ereimede at the time of renewal. please
Include an Application for Revision with the renewal application.

Problems: If Issues should arise me the conduct or the research. such as unanticipated problems. adverse
events. or any problem that may increase the risk to the human subiects. notify the IRB oﬂice promptly. Forms

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PieaseusetheIRBnumberiistedaboveonanyfonnssubmittedwhichreiatetothisprolect.oronany
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Good luck In your research. Ifwe can be ofhrrther assistance, please contact us at 517-355-2180 or via email
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157

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158

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