Association Between Maternal-Perceived Psychological Stress and Fetal Telomere Length.

OBJECTIVE: Our study aimed to investigate the association between maternal-perceived psychological stress and fetal telomere length. METHODS: We recruited women in labor upon hospital delivery admission. Based on responses to the Perceived Stress Scale, we categorized participants as having "high," "normal," or "low" perceived stress. We collected umbilical cord blood samples (N = 71) and isolated genomic DNA from cord blood leukocytes using quantitative polymerase chain reaction. We used a ratio of relative telomere length derived by telomere-to-single-copy gene ratio (T/S ratio). We applied analysis of variance and bootstrapping statistical procedures. RESULTS: Sixteen (22.5%) women were classified as having low perceived stress, 42 (59.2%) were classified as having normal perceived stress, and 13 (18.3%) were classified as having high perceived stress. Fetal telomere length differed significantly across the three stress groups in a dose-response pattern (T/S ratio of those with low perceived stress was greater than those with normal perceived stress, which was greater than those with high perceived stress [P < 0.05]). CONCLUSIONS: Our findings support our hypothesis that maternal-perceived psychological stress during pregnancy is associated with shorter fetal telomere length and suggest maternal stress as a possible marker for early intrauterine programming for accelerated chromosomal aging.

Impact of intrauterine tobacco exposure on fetal telomere length.

OBJECTIVE: We sought to investigate whether maternal smoking during pregnancy affects telomere length of the fetus. STUDY DESIGN: Pregnant women were recruited on hospital admission at delivery. A self-report questionnaire and salivary cotinine test were used to confirm tobacco exposure. Neonatal umbilical cord blood samples were collected, and genomic DNA was isolated from cord blood leukocytes and was analyzed for fetal telomere length based on quantitative polymerase chain reaction. A ratio of relative telomere length was determined by telomere repeat copy number and single copy gene copy number (T/S ratio) and used to compare the telomere length of active, passive, and nonsmokers. Bootstrap and analysis of variance statistical methods were used to evaluate the relationship between prenatal smoking status and fetal telomere length. RESULTS: Of the 86 women who were included in this study, approximately 69.8% of the participants were covered by Medicaid, and 55.8% of the participants were black or Hispanic. The overall mean T/S ratio was 0.8608 ± 1.0442. We noted an inverse relationship between smoking and fetal telomere length in a dose-response pattern (T/S ratio of nonsmokers that was more than passive smokers that was more than active smokers). Telomere length was significantly different for each pairwise comparison, and the greatest difference was between active and nonsmokers. CONCLUSION: Our results provide the first evidence to demonstrate a positive association between shortened fetal telomere length and smoking during pregnancy. Our findings suggest the possibility of early intrauterine programming for accelerated aging that is the result of tobacco exposure.

Fetal sex and differential survival in preeclampsia and eclampsia.

PURPOSE: We investigate sex differences in the incidence of stillbirth, neonatal mortality, and perinatal mortality among singletons born to mothers with preeclampsia or eclampsia. METHODS: Retrospective cohort analysis of a population-based sample of singleton births covering the period 1989 through 2005 (n = 56,313). RESULTS: The study population comprised 26,931 female (47.8%) and 29,382 male infants (52.2%; referent group). Overall, the prevalence of stillbirth, neonatal mortality and perinatal mortality were 0.68, 0.52 and 1.2%, respectively. There was no sex difference in the incidence of stillbirth, neonatal or perinatal mortality among offspring of mothers in this study. CONCLUSION: Although there was a preponderance of male infants among mothers with preeclampsia or eclampsia, we did not observe any sex-associated differences in fetal or neonatal survival among offspring of mothers with preeclampsia or eclampsia.

Assessing the impact of paternal involvement on racial/ethnic disparities in infant mortality rates.

We sought to assess the contribution of paternal involvement to racial disparities in infant mortality. Using vital records data from singleton births in Florida between 1998 and 2005, we generated odds ratios (OR), 95% confidence intervals (CI), and preventative fractions to assess the association between paternal involvement and infant mortality. Paternal involvement status was based on presence/absence of paternal first and/or last name on the birth certificate. Disparities in infant mortality were observed between and within racial/ethnic subpopulations. When compared to Hispanic (NH)-white women with involved fathers, NH-black women with involved fathers had a two-fold increased risk of infant mortality whereas infants born to black women with absent fathers had a seven-fold increased risk of infant mortality. Elevated risks of infant mortality were also observed for Hispanic infants with absent fathers (OR = 3.33. 95%CI = 2.66-4.17). About 65-75% of excess mortality could be prevented with increased paternal involvement. Paternal absence widens the black-white gap in infant mortality almost four-fold. Intervention programs to improve perinatal paternal involvement may decrease the burden of absent father-associated infant mortality.

Alcohol consumption during pregnancy and risk of placental abruption and placenta previa.

The purpose of this study was to examine the association between prenatal alcohol consumption and the occurrence of placental abruption and placenta previa in a population-based sample. We used linked birth data files to conduct a retrospective cohort study of singleton deliveries in the state of Missouri during the period 1989 through 2005 (n = 1,221,310). The main outcomes of interest were placenta previa, placental abruption and a composite outcome defined as the occurrence of either or both lesions. Multivariate logistic regression was used to generate adjusted odd ratios, with non-drinking mothers as the referent category. Women who consumed alcohol during pregnancy had a 33% greater likelihood for placental abruption during pregnancy (adjusted odds ratio (OR), 95% confidence interval (CI) = 1.33 [1.16-1.54]). No association was observed between prenatal alcohol use and the risk of placenta previa. Alcohol consumption in pregnancy was positively related to the occurrence of either or both placental conditions (adjusted OR [95% CI] = 1.29 [1.14-1.45]). Mothers who consumed alcohol during pregnancy were at elevated risk of experiencing placental abruption, but not placenta previa. Our findings underscore the need for screening and behavioral counseling interventions to combat alcohol use by pregnant women and women of childbearing age.

Interpregnancy body mass index changes and risk of stillbirth.

BACKGROUND/AIMS: To examine the association between interpregnancy body mass index (BMI) change and stillbirth. METHODS: Retrospective study using Missouri maternally linked cohort files (1978-2005). A total of 218,389 women were used in the analysis. BMI was classified as: underweight (<18.5), normal (18.5-24.9), overweight (25-29.9), or obese (≥30.0). Weight change was defined based on BMI category (i.e. normal-normal, normal-obese, etc.). Cox proportional hazard regression models were used to generate adjusted hazard ratios (HR) and 95% CI for the risk of stillbirth in the second pregnancy. RESULTS: Significant findings were associated with interpregnancy BMI changes involving overweight mothers becoming obese (HR = 1.4, 95% CI 1.1-1.7), normal-weight mothers becoming overweight (HR = 1.2, 95% CI 1.0-1.4) or obese (HR = 1.5, 95% CI 1.1-2.1), or obese mothers maintaining their obesity status across the two pregnancies (HR = 1.4, 95% CI 1.2-1.7). Other weight change categories did not show significant risk elevation for stillbirth. CONCLUSIONS: BMI change appears to play an important role in subsequent stillbirth risk.

Changes in prepregnancy body mass index between pregnancies and risk of preterm phenotypes.

We examined whether the risk of preterm birth and its subtypes (medically indicated and spontaneous preterm) are influenced by changes in prepregnancy body mass index (BMI) between the first and second pregnancies. A population-based, retrospective cohort analysis was performed using the Missouri (1978 to 2005) longitudinally linked cohort data sets. Women with their first two successive singleton live births ( N = 436,502) were analyzed. The risks for preterm birth and its subtypes were evaluated using multivariate logistic regression modeling. Compared with women who maintained normal interpregnancy BMI, women who lowered their weight from normal to underweight were more likely to experience preterm and spontaneous preterm birth (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.4 to 1.6). Women with BMI changes from normal weight to obese (OR 1.4, 95% CI 1.2 to 1.6) and normal weight to overweight (OR 1.2, 95% CI 1.1 to 1.3) were at increased risk of medically indicated preterm birth. A decrease in prepregnancy BMI from normal to underweight is associated with increased risk of spontaneous preterm birth, and prepregnancy BMI increases from normal to overweight or to obese BMI are associated with increased risk of medically indicated preterm birth.

The impact of previous cesarean section on the success of future fetal programming pattern.

PURPOSE: The purpose of this study is to examine whether cesarean section in the first pregnancy is associated with the success or failure of programmed fetal growth phenotypes or patterns in the subsequent pregnancy. METHODS: We analyzed data from a population-based retrospective cohort of singleton deliveries that occurred in the state of Missouri from 1978 to 2005 (n = 1,224,133). The main outcome was neonatal mortality, which was used as an index of the success of fetal programming. Cox proportional hazard and logistic regression models were used to generate point estimates and 95% confidence intervals. RESULTS: Mothers delivering by cesarean section in the first pregnancy were less likely to deliver subsequent appropriate-for-gestational-age (AGA) neonates (OR 0.91, 95% CI 0.89-0.92) when compared with mothers delivering vaginally. Of the 1,457 neonatal deaths in the second pregnancy, 383 early neonatal and 95 late neonatal deaths were to mothers with cesarean section deliveries in the first pregnancy. When compared with women with a previous vaginal delivery, AGA neonates of women with a primary cesarean section had 20% increased risk of both neonatal (OR 1.20, 95% CI 1.05-1.37) and early neonatal (OR 1.23, 95% CI 1.05-1.43) death. CONCLUSION: Our study suggests that previous cesarean section is a risk factor for neonatal mortality among AGA infants of subsequent pregnancy. Future prospective studies are needed to confirm these findings.

The psychosocial impact of vesico-vaginal fistula in Niger.

PURPOSE: To explore the psycho-social impact of vesico-vaginal fistula (VVF) on women in Niger. STUDY DESIGN: We conducted a qualitative study on 21 women in convalescence at the DIMOL Reproductive Health Center in Niamey, Niger, in 2008 and 2009. The women had undergone 1-3 fistula repair operations and all had stillborn infants. RESULTS: Women reported many psychological consequences of VVF including depression, feelings of shame, and loneliness. Others reported feeling devalued as a woman and wanting to end their lives. Social consequences of fistula reported by these women included rejection from society, isolation, rejection from husband and/or divorce. Almost half of the women reported of having lost their social network and support as a result of the fistula. Women with VVF were deemed unworthy, and their illness was often attributed to some fault of their own. CONCLUSIONS: Our findings support the notion that socio-economic factors, though they certainly contribute to obstetric fistula, are not the primary reason for fistula, particularly in Niger. Fistula is a direct result of lack of access to skilled birth attendants and emergency obstetric care.

Association between tobacco use in pregnancy and placenta-associated syndromes: a population-based study.

INTRODUCTION: Cigarette smoking is an established risk factor for adverse perinatal outcomes. The purpose of this study is to examine the association between maternal smoking in pregnancy and the occurrence of placental-associated syndromes (PAS). METHODS: We analyzed data from a population-based retrospective cohort of singleton deliveries that occurred in the state of Missouri from 1989 through 2005 (N = 1,224,133). The main outcome was PAS, a composite outcome defined as the occurrence of placental abruption, placenta previa, preeclampsia, small for gestational age, preterm or stillbirth. We used logistic regression models to generate adjusted odd ratios and their 95 percent confidence intervals. Non-smoking gravidas served as the referent category. RESULTS: The overall prevalence of prenatal smoking was 19.6%. Cigarette smoking in pregnancy was associated with the composite outcome of placental syndromes (odds ratio, 95% confidence interval = 1.59, 1.57-1.60). This association showed a dose-response relationship, with the risk of PAS increasing with increased quantity of cigarettes smoked. Similar results were observed between smoking in pregnancy and independent risks for abruption, previa, SGA, stillbirth, and preterm delivery. CONCLUSION: Maternal smoking in pregnancy is a risk factor for the development of placenta-associated syndrome. Smoking cessation interventions in pregnancy should continue to be encouraged in all maternity care settings.

Feto-infant health and survival: does paternal involvement matter?

Lack of paternal involvement during pregnancy and infancy may account for a significant burden of the adverse pregnancy outcomes among black women and could therefore, represent an important avenue providing the opportunity to improve feto-infant health and survival. This study aimed to review the literature on paternal involvement during the perinatal period and its influence on feto-infant health and survival. Literature for this review was identified by searching the PubMed database from the National Center for Biotechnology Information at the US National Library of Medicine as well as the ISI Web of Knowledge Databases, OVID, and CINAHL. A total of seven papers were identified and included in this review. There is paucity of data in this domain. Overall findings suggest that paternal involvement during pregnancy may have important implications for maternal prenatal health behaviors and feto-infant health. Although results are limited, results suggest that paternal involvement has a positive influence on prenatal care usage, abstinence from alcohol and smoking, and a reduction in low birth weight and small for gestational age infants. None of the papers examined the relationship between stillbirth and paternal involvement. Additional studies with enhanced measures of paternal involvement are needed to better assess the role of fathers in enhancing prenatal health behaviors and pregnancy outcomes. Efforts should be made to include fathers in future studies and reduce reliance on maternal report and to investigate paternal roles across different racial groups so that appropriate interventions can be developed.

The impact of paternal involvement on feto-infant morbidity among Whites, Blacks and Hispanics.

Few studies have examined paternal involvement in relation to feto-infant health; therefore we aim to assess the impact of absence of the father on birth outcomes among racial-ethnic subgroups. Florida vital statistics records for singleton births occurring between 1998 and 2005 were used for this study. Births to women less than 20 years of age and births outside the gestational age range of 20-44 weeks were excluded. Adjusted and unadjusted odds ratios and 95% confidence intervals were generated to examine the impact of paternal involvement, as defined by presence of paternal information on the birth certificate, on feto-infant morbidity across racial-ethnic sub-populations. There were higher rates of low birth weight, very low birth weight, preterm birth, very preterm birth, and small for gestational age (SGA) among father-absent births. Within each racial-ethnic subgroup, women with absent fathers had higher risks of poor birth outcomes than their counterparts with involved fathers. Black women with absent fathers had the highest risk of low birth weight, very low birth weight, preterm birth, very preterm birth, and SGA. Promoting paternal involvement during the perinatal period may provide a means to decrease the proportion of infants born of very low birth weight or very preterm, thus potentially reducing the black-white disparity in infant mortality.

Intrauterine exposure to tobacco and risk of medically indicated and spontaneous preterm birth.

We investigated the association between prenatal smoking and the occurrence of medically indicated and spontaneous preterm delivery (<37 weeks). We performed a retrospective cohort study of singleton live births in the state of Missouri (n = 1,219,159) using maternally linked cohort data files covering the period 1989 to 2005. The main outcomes of interest were spontaneous and medically indicated preterm and very preterm birth. Logistic regression models were used to generate adjusted odds ratios and their 95% confidence intervals. There were 132,246 (10.8%) infants born preterm in the study population, of which 106,410 (80.5%) were classifiable as spontaneous preterm births and 25,836 (19.5%) were medically indicated preterm deliveries. We found elevated risks for both medically indicated and spontaneous preterm birth associated with maternal cigarette smoking during pregnancy. This heightened risk was particularly evident for medically indicated preterm birth (adjusted odds ratio [95% confidence interval] = 1.48 [1.41 to 1.55]). Women who smoke during pregnancy are at increased risk for preterm birth, and especially for medically indicated preterm delivery.

The impact of obesity on spontaneous and medically indicated preterm birth among adolescent mothers.

PURPOSE: We sought to evaluate the impact of obesity on the risk of spontaneous and medically indicated preterm birth in young women compared to adult women. METHODS: Florida vital records from 2004 to 2007 were used to obtain data. The study sample consisted of 290,807 mothers of whom 4,739 were adolescent girls < or =15 years old: 23,228 were girls 16-17 years old; 58,196 were women 18-19 years old; and 204,644 were women 20-24 years old. Adjusted estimates for spontaneous and medically indicated preterm birth were determined based on maternal BMI and weight gain during pregnancy. Subjects were categorized by BMI as follows: class I obesity (30.0 < or = BMI < or = 34.9), class II obesity (35.0 < or = BMI < or = 39.9), class III obesity (40 < or = BMI < or = 49.9), and super-obese (BMI > or = 50.0). RESULTS: Obese mothers had elevated risk for medically indicated preterm birth and lower risk for spontaneous preterm birth compared to non-obese mothers. Overall, the risk for spontaneous preterm birth increased in a dose-dependent fashion with younger age but no age-dependent trend was observed for medically indicated preterm birth (P < 0.0001). Very low weight gain (<0.12 kg/week) during pregnancy was associated with a higher risk of spontaneous preterm birth among both non-obese and obese teenagers. CONCLUSIONS: Preterm birth is a heterogeneous entity that is mediated by obesity status and maternal age. Obesity among pregnant teenagers increases the risk for medically indicated preterm birth but not the risk for spontaneous preterm birth.

The superobese mother and ethnic disparities in preterm birth.

OBJECTIVES: We assessed the association between preterm birth and obesity subtypes across racial/ethnic groups. METHODS: We analyzed data on 540981 women from birth cohort files for the State of Florida from 2004 to 2007. Obese women were categorized using body mass index (BMI) values as class I obese (30.0 < or = BMI < or = 34.9), class II obese (35.0 < or = BMI < or = 39.9), class III or extremely obese (40 < or = BMI < or = 49.9), and superobese (BMI > or = 50.0). Logistic regression was used to obtain adjusted estimates. RESULTS: About 28% of women were obese, with the highest rate (40.9%) registered among black gravidas, while whites and Hispanics had comparable rates (24.3% vs 25.5%, respectively). Superobesity was also most prevalent in blacks (1.3%). Among obese women, the risk for preterm birth was greatest among blacks (OR, 1.71; 95% CI, 1.65-1.77), while whites (OR, 1.15; 95% CI, 1.12-1.19) and Hispanics (OR, 1.22; 95% CI, 1.18-1.27) had significantly lower and comparable risk levels. CONCLUSIONS: Extremely obese and superobese women are emerging high-risk groups for adverse birth outcomes, and black women appear to bear the heaviest burden. The disproportionately rising trend in extreme forms of obesity among black women is of utmost concern and represents a clarion call for infusion of more resources into obesity prevention programs in black communities.

Socio-ecological Model as a Framework for Overcoming Barriers and Challenges in Randomized Control Trials in Minority and Underserved Communities.

BACKGROUND: Numerous barriers and challenges can hinder the successful enrollment and retention of study participants in clinical trials targeting minority populations. To conduct quality research, it is important to investigate these challenges, determine appropriate strategies that are evidence-based and continue seeking methods of improvement. METHODS: In this paper, we report such experiences in a registered clinical trial in an underserved minority population in the Southern part of United States. This research study is a randomized double-blind controlled clinical trial that tests the efficacy of higher-strength as compared to low-strength/standard of care folic acid to prevent fetal body and brain size reduction in pregnant women who smoke. A unique approach in this socio-behavioral, genetic-epigenetic clinical trial is that we have adopted the socio-ecological model as a functional platform to effectively achieve and maintain high participant recruitment and retention rates. RESULTS: We highlight the barriers we have encountered in our trial and describe how we have successfully applied the socio-ecological model to overcome these obstacles. CONCLUSIONS AND GLOBAL HEALTH IMPLICATIONS: Our positive experience will be of utility to other researchers globally. Our fi ndings have far-reaching implications as the socio-ecological model approach is adaptable to developed and developing regions and has the potential to increase recruitment and retention of hard-to-reach populations who are typically under-represented in clinical trials.

Paternal involvement and fetal morbidity outcomes in HIV/AIDS: a population-based study.

Prior research indicates that infants with absent fathers are vulnerable to unfavorable fetal birth outcomes. HIV is a recognized risk factor for adverse birth outcomes. However, the influence of paternal involvement on fetal morbidity outcomes in women with HIV remains poorly understood. Using linked hospital discharge data and vital statistics records for the state of Florida (1998-2007), the authors assessed the association between paternal involvement and fetal growth outcomes (i.e., low birth weight [LBW], very low birth weight [VLBW], preterm birth [PTB], very preterm birth [VPTB], and small for gestational age [SGA]) among HIV-positive mothers (N=4,719). Propensity score matching was used to match cases (absent fathers) to controls (fathers involved). Conditional logistic regression was employed to generate adjusted odds ratios (OR). Mothers of infants with absent fathers were more likely to be Black, younger (<35 years old), and unmarried with at least a high school education (p<.01). They were also more likely to have a history of drug (p<.01) and alcohol (p=.02) abuse. These differences disappeared after propensity score matching. Infants of HIV-positive mothers with absent paternal involvement during pregnancy had elevated risks for adverse fetal outcomes (LBW: OR=1.30, 95% confidence interval [CI]=1.05-1.60; VLBW: OR=1.72, 95% CI=1.05-2.82; PTB: OR=1.38, 95% CI=1.13-1.69; VPTB: OR=1.81, 95% CI=1.13-2.90). Absence of fathers increases the likelihood of adverse fetal morbidity outcomes in women with HIV infection. These findings underscore the importance of paternal involvement during pregnancy, especially as an important component of programs for prevention of mother-to-child transmission of HIV.

Association between maternal symptoms of sleep disordered breathing and fetal telomere length.

STUDY OBJECTIVES: Our investigation aims to assess the impact of symptoms of maternal sleep-disordered breathing, specifically sleep apnea risk and daytime sleepiness, on fetal leukocyte telomere length. PARTICIPANTS AND SETTING: Pregnant women were recruited upon hospital delivery admission. INTERVENTIONS: Sleep exposure outcomes were measured using the Berlin Questionnaire to quantify sleep apnea and the Epworth Sleepiness Scale to measure daytime sleepiness. Participants were classified as "High Risk" or "Low Risk" for sleep apnea based on responses to the Berlin, while "Normal" or "Abnormal" daytime sleepiness was determined based on responses to the Epworth. DESIGN: Neonatal umbilical cord blood samples (N = 67) were collected and genomic DNA was isolated from cord blood leukocytes using Quantitative PCR. A ratio of relative telomere length was derived by telomere repeat copy number and single copy gene copy number (T/S ratio) and used to compare telomere lengths. Bootstrap and ANOVA statistical procedures were employed. MEASUREMENTS AND RESULTS: On the Berlin, 68.7% of participants were classified as Low Risk while 31.3% were classified as High Risk for sleep apnea. According to the Epworth scale, 80.6% were determined to have Normal daytime sleepiness, and 19.4% were found to have Abnormal daytime sleepiness. The T/S ratio among pregnant women at High Risk for sleep apnea was significantly shorter than for those at Low Risk (P value < 0.05), and the T/S ratio among habitual snorers was significantly shorter than among non-habitual snorers (P value < 0.05). Although those with Normal Sleepiness had a longer T/S ratio than those with Abnormal Sleepiness, the difference was not statistically significant. CONCLUSION: Our results provide the first evidence demonstrating shortened telomere length among fetuses exposed to maternal symptoms of sleep disordered breathing during pregnancy, and suggest sleep disordered breathing as a possible mechanism of accelerated chromosomal aging.

HIV infection and its impact on fetal outcomes among women of advanced maternal age: a propensity score weighted matching approach.

Advanced maternal age (AMA) and HIV status have been investigated separately for their influence on infant outcomes. Both are associated with adverse fetal growth outcomes, including low birth weight (LBW) and preterm birth (PTB). However, the impact of the cooccurrence of these factors in relation to birth outcomes remains relatively understudied. We analyzed Florida hospital discharge data linked to vital records. The study population consisted of women who had a singleton live birth between 1998 and 2007 (N=1,687,176). The exposure variables were HIV infection and maternal age, while the outcomes of interest were LBW, PTB, and small for gestational age (SGA). We matched HIV-positive women to HIV-negative women on selected variables using propensity scores. To approximate relative risks, we computed adjusted odds ratios (AOR) and 95% confidence intervals (CI) generated from logistic regression models and accounted for the matched design using the generalized estimating equations framework. After adjusting for demographic variables, clinical conditions, and route of birth, the risks of LBW, PTB, and SGA remained significant for HIV-positive women, regardless of age. HIV-positive women of AMA (≥35 years) were more likely to have infants of LBW (AOR=1.73, 95% CI=1.37-2.18), PTB (AOR=1.35, 95% CI: 1.06-1.71), and SGA (AOR=1.52, 95% CI=1.22-1.89), compared to uninfected mothers of younger age (<35 years). For women of advanced age, HIV positivity elevates their risk for LBW and PTB. The interplay of HIV status and age should be considered by healthcare providers when determining appropriate interconception strategies for women and their families.

Placental abruption, offspring sex, and birth outcomes in a large cohort of mothers.

OBJECTIVE: To investigate stillbirth, neonatal, and perinatal death outcomes in pregnancies complicated by placental abruption, according to fetal sex. METHODS: We utilized maternally linked cohort data files of singleton live births to mothers diagnosed with placental abruption during the period 1989 through 2005 (n = 10,014). Logistic regression models were employed to generate adjusted odd ratios and their 95% confidence intervals. Male babies served as the referent category. RESULTS: The sex ratio at birth was 1.18. The overall prevalence of stillbirth, neonatal mortality, and perinatal mortality was 7.2%, 4.5%, and 11.8%, respectively. Placental abruption was less likely to occur in mothers carrying female pregnancies than mothers of male infants (adjusted odds ratio [95% confidence interval] = 0.89 [0.86-0.93]). There were no significant sex differences with regards to stillbirth, neonatal mortality, and perinatal mortality. Similar findings were observed for preterm and term infants. CONCLUSIONS: Although a preponderance of male infants was discernable among mothers with placental abruption, no sex difference in fetal survival was observed among the offspring of the mothers affected by placental abruption.