The association between maternal and paternal race and preterm birth.

BACKGROUND: Non-Hispanic black maternal race is a known risk factor for preterm birth. However, the contribution of paternal race is not as well established. OBJECTIVE: We sought to evaluate the risk of preterm birth among non-Hispanic black, non-Hispanic white, and mixed non-Hispanic black and non-Hispanic white dyads. STUDY DESIGN: This was a population-based cohort study of all live births in the United States from 2015 to 2017, using live birth records from the National Vital Statistics System. Singleton, nonanomalous infants whose live birth record included maternal and paternal self-reported race as either non-Hispanic white or non-Hispanic black were included. The primary outcome was preterm birth at <37 weeks' gestation; secondary outcomes included preterm birth at <34 and <28 weeks' gestation and delivery gestational age (as a continuous variable). Data were analyzed using chi-square, t test, analysis of variance, and logistic regression. A Kaplan-Meier survival curve was also generated. RESULTS: There were 11,809,599 live births during the study period; 4,008,622 births met the inclusion criteria. Of included births, 291,647 (7.3%) occurred at <37 weeks' gestation. Using the convention of maternal race first followed by paternal race, preterm birth at <37 weeks' gestation was most common among non-Hispanic black and non-Hispanic black dyads (n=70,987 [10.8%]), followed by non-Hispanic black and non-Hispanic white (n=3137 [9.5%]), non-Hispanic white and non-Hispanic black (n=9136 [8.3%]), and non-Hispanic white and non-Hispanic white dyads (n=209,387 [6.5%]; P<.001 for trend). Births at <34 weeks' (n=74,474) and <28 weeks' gestation (n=18,474) were also more common among non-Hispanic black and non-Hispanic black dyads. Specifically, 24,351 (3.7%) non-Hispanic black and non-Hispanic black, 1017 (3.1%) non-Hispanic black and non-Hispanic white, 2408 (2.2%) non-Hispanic white and non-Hispanic black, and 46,698 non-Hispanic white and non-Hispanic white dyads delivered at <34 weeks' gestation, and 7988 non-Hispanic black and non-Hispanic black (1.2%), 313 (1.0%) non-Hispanic black and non-Hispanic white, 584 (0.5%) non-Hispanic white and non-Hispanic black, and 9589 (0.3%) non-Hispanic white and non-Hispanic white dyads delivered at <28 weeks' gestation. Non-Hispanic white and non-Hispanic white dyads delivered at a mean 38.8± standard deviation of 1.7 weeks' gestation, although non-Hispanic white and non-Hispanic black, non-Hispanic black and non-Hispanic white, and non-Hispanic black and non-Hispanic black dyads delivered at 38.6±2.0, 38.5±2.3, and 38.3±2.4 weeks' gestation, respectively (P<.001). Adjusted odds ratios for the association between maternal or paternal race and preterm birth were highest for non-Hispanic black and non-Hispanic black dyads at each gestational age cutoff: adjusted odds ratio, 1.60 (95% confidence interval, 1.11-1.19) (<37 weeks' gestation); adjusted odds ratio, 2.47 (95% confidence interval, 2.41-2.53) (<34 weeks' gestation); and adjusted odds ratio, 4.22 (95% confidence interval, 4.04-4.41) (<28 weeks' gestation) compared with the non-Hispanic white referent group. Models adjusted for insurance status, chronic hypertension, tobacco use during pregnancy, history of previous preterm birth, and male fetus. In the Kaplan-Meier survival analysis, non-Hispanic black and non-Hispanic black dyads delivered the earliest across the range of delivery gestational ages compared with all other combinations of dyads. CONCLUSION: Non-Hispanic black paternal race is a risk factor for preterm birth and should be considered when evaluating maternal a priori risk of prematurity. Future research should investigate the mechanisms behind this finding, including determining the contribution of factors, such as racism, maternal and paternal genetics, and epigenetics to an individual's risk of preterm birth.

The association of age at menopause and all-cause and cause-specific mortality by race, postmenopausal hormone use, and smoking status.

While a mean age at menopause of 51 years has been reported in the United States (U.S.), some U.S. women experience menopause before age 45, possibly increasing risk of cardiovascular mortality; however, the role in all-cause and cerebrovascular-related mortality is unclear. The purpose of this study was to investigate the association between age at menopause and all-cause and cause-specific mortality by race, hormone replacement therapy (HRT) use, and smoking status. REasons for Geographic and Racial Differences in Stroke (REGARDS) is a population-based study of 30,239 participants aged ≥45 years enrolled between 2003 and 2007 of whom 14,361 were postmenopausal women. Age at menopause was defined as <45 (early) or ≥45. All-cause and cause-specific mortality were ascertained through 2013. Cox proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) for the association between age at menopause and mortality, adjusting for baseline measures. Of 11,287 eligible women (6403 white; 4884 black), mean menopause age was 45.2 (SD 7.9) with 1524 deaths over 7.1 years. Significant interactions were detected between early age at menopause (39%) and HRT use in association with all-cause mortality (p < 0.01), mortality from coronary heart disease (p = 0.06), and mortality from all other causes (p = 0.04). An association between early age at menopause and all-cause mortality was observed among ever-HRT users (HR = 1.31, 95% CI: 1.10-1.56), but not never-HRT users (HR = 1.01, 95% CI: 0.85-1.20). There were no differences in associations examined by race or smoking status. Increased all-cause mortality risk was observed for ever-HRT users with menopause before age 45.

Maternal diabetes and hypertensive disorders in association with autism spectrum disorder.

Previous studies have shown complications of pregnancy, often examined in aggregate, to be associated with autism spectrum disorder (ASD). Results for specific complications, such as maternal diabetes and hypertension, have not been uniformly consistent and should be investigated independently in relation to ASD in a large community-based sample. The Study to Explore Early Development (SEED), a US multisite case-control study, enrolled children born in 2003-2006 at 2-5 years of age. Children were classified into three groups based on confirmation of ASD (n = 698), non-ASD developmental delay (DD; n = 887), or controls drawn from the general population (POP; n = 979). Diagnoses of any diabetes or hypertensive disorder during pregnancy were identified from prenatal medical records and maternal self-report. Logistic regression models estimated adjusted odds ratios (aOR) and confidence intervals (CI) adjusting for maternal age, race/ethnicity, education, smoking during pregnancy, and study site. Models for hypertension were additionally adjusted for parity and plurality. Among 2,564 mothers, we identified 246 (9.6%) with any diabetes and 386 (15.1%) with any hypertension in pregnancy. After adjustment for covariates, any diabetes during pregnancy was not associated with ASD (aOR = 1.10 [95% CI 0.77, 1.56]), but any hypertension was associated with ASD (aOR = 1.69 [95% CI 1.26, 2.26]). Results were similar for DD, and any diabetes (aOR = 1.29 [95% CI 0.94, 1.78]) or any hypertension (aOR = 1.71 [95% CI 1.30, 2.25]). Some pregnancy complications, such as hypertension, may play a role in autism etiology and can possibly serve as a prompt for more vigilant ASD screening efforts. Autism Res 2019, 12: 967-975. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: We studied if common complications in pregnancy are associated with autism spectrum disorder (ASD) in a large sample of mothers and children. Our results show an association between conditions marked by high blood pressure and ASD, but no association with conditions marked by high blood sugar and ASD. Associations were similar for children who had a developmental disorder that was not ASD, suggesting that this relationship may not be specific to ASD.

Sex-Specific Differences in Late Preterm Neonatal Outcomes.

OBJECTIVE: To estimate sex-specific differences in late preterm outcomes and evaluate whether betamethasone modifies this association. STUDY DESIGN: We conducted a secondary analysis of a multicenter trial of women at risk for late preterm birth randomized to receive betamethasone or placebo. We included women who delivered at 34 to 37 weeks and excluded major fetal anomalies. The primary outcome was severe neonatal morbidity (mechanical ventilation, respiratory distress syndrome, bronchopulmonary dysplasia, sepsis, necrotizing enterocolitis, and intraventricular hemorrhage). Maternal characteristics were compared using chi-square test, t-test, or Mann-Whitney U-test. Multivariable logistic regression estimated the association between sex and morbidity, and likelihood ratio testing assessed for effect modification by betamethasone. RESULTS: Of 2,831 women in the primary trial, 2,331 met the inclusion criteria: 1,236 delivered males and 1,095 delivered females. Betamethasone modified the association between sex and severe morbidity (p = 0.047). Among those who received betamethasone, male sex was associated with higher odds of severe morbidity (adjusted odds ratio: 1.95, 95% confidence interval: 1.25-3.05), compared with female sex. Among those who did not receive betamethasone, there was no significant association between sex and morbidity. CONCLUSION: Male sex is a risk factor for adverse late preterm outcomes, including severe neonatal morbidity after betamethasone receipt.

Emergency Care Utilization Among Pregnant Medicaid Recipients in North Carolina: An Analysis Using Linked Claims and Birth Records.

Objectives To estimate the rate of pregnancy-associated emergency care visits and identify maternal and pregnancy characteristics associated with high utilization of emergency care among pregnant Medicaid recipients in North Carolina. Methods A retrospective cohort study using linked Medicaid hospital claims and birth records of 107,207 pregnant Medicaid recipients who delivered a live-born infant in North Carolina between January 1, 2008 and December 31, 2009. Rates were estimated per 1000 member months of Medicaid coverage. High utilization was defined as ≥ 4 visits. Emergency care visits included encounters in the emergency department or obstetric triage unit during pregnancy that did not result in hospital admission. Results During the study period, 57.5% of pregnant Medicaid recipients sought emergency care at least once during pregnancy. There were 171,909 emergency care visits with an overall rate of 202.3 visits per 1000 member months. Among the subset of pregnant women with Medicaid coverage for the majority of their pregnancy (n = 75,157), 18.1% were high utilizers. High emergency care utilization was associated with young age, black race, lower education, tobacco use, late preterm delivery, multifetal gestation, and having ≥ 1 comorbidity. Threatened labor and abdominal pain were the leading indications for visits. Conclusion Utilization of hospital-based emergency care services was common in this cohort of pregnant Medicaid recipients. Additional research is needed to assess the drivers for accessing care through the emergency department, and to examine differences in pregnancy outcomes and health care costs between high and low utilizers.

Cardiovascular Health of Mothers in the United States: National Health and Nutrition Examination Survey 2007-2014.

Background: Pregnancy and childrearing can impact women's health and alter chronic disease trajectories in later life, including cardiovascular disease. The purpose of this study was to assess measures of women's cardiovascular health by time since last live birth. Materials and Methods: Data were from 4,021 nonpregnant U.S. women, 20-44 years of age, participating in the 2007-2014 National Health and Nutrition Examination Survey (NHANES). Cardiovascular health was assessed using physical measures, laboratory measures, self-reported behaviors, medical conditions, and selected psychosocial factors by time since last live birth. Results: Women reported their last live birth within the past 12 months ("mothers of infants"; 7.4%), >12 months, but <3 years ago ("mothers of toddlers"; 10.0%), or ≥3 years ago ("mothers of older children"; 45.2%); 37.3% were nulliparous. Compared with nulliparous women, mothers of older children had a higher prevalence of selected cardiovascular risk factors, including unhealthy diet (75.6% vs. 68.8%) and smoking (28.1% vs. 21.9%), after adjustment for sociodemographics (including age). Mothers of toddlers had a higher prevalence of unhealthy diet (78.0% vs. 68.8%). Mothers also had poorer metabolic health as indicated by a higher prevalence of low HDL cholesterol among mothers of toddlers and older children (44.2% and 40.4%, respectively, vs. 33.6%), and a higher prevalence of high waist circumference among mothers of infants (65.6% vs. 53.8%). Some mothers also had a higher prevalence of other cardiovascular risk factors, including low physical activity and poor sleep. Conclusion: Prior pregnancy and childrearing may be associated with selected cardiovascular risk factors among nonpregnant reproductive-aged U.S. women.

Higher number of live births is associated with left ventricular diastolic dysfunction and adverse cardiac remodelling among US Hispanic/Latina women: results from the Echocardiographic Study of Latinos.

INTRODUCTION: Female sex is a risk factor for heart failure with preserved ejection fraction (HFpEF). Previous literature suggests that some diastolic dysfunction (DD) develops during pregnancy and may persist postdelivery. Our objective was to examine the relationship between parity and cardiac structure and function in a population-based cohort. METHODS: Participants included 1172 Hispanic/Latina women, aged ≥45 years, enrolled in the Echocardiographic Study of Latinos from four US communities (Bronx, Miami, San Diego and Chicago). Standard echocardiographic techniques were used to measure cardiac volumes, left ventricular mass, systolic and diastolic function. Using sampling weights and survey statistics, multivariable linear and logistic regression models were constructed adjusting for age, body mass index, diabetes or prediabetes, systolic blood pressure, use of antihypertensive medications, smoking, total cholesterol and high-density lipoprotein cholesterol. RESULTS: In the target population, 5.0% were nulliparous (no live births) and 10.5% were grand multiparous (≥5 live births). Among the nulliparous women, 46% had DD as compared with 51%-58% of women with 1-4 live births and 81% of women with ≥5 live births (p<0.01). In full multivariate models, higher parity was significantly associated with greater left ventricular end-systolic volumes, end-diastolic volumes, left atrial volume indices and presence of DD (all p<0.01) but was not associated with ejection fraction. The log odds for having any grade of DD in grand-multiparous women was over three times that seen in nulliparous women (OR=3.4, 95% CI 1.5 to 7.9, p<0.01) in models further adjusted for income and education. CONCLUSIONS: Higher parity is associated with increased cardiac mass, volumes and the presence of DD. Further studies are needed to elucidate this apparent deleterious relation and whether parity can help explain the increased risk of HFpEF in women.

Gestational age at initiation of 17-alpha hydroxyprogesterone caproate and recurrent preterm birth.

BACKGROUND: Preterm birth is the leading cause of neonatal morbidity and mortality in nonanomalous neonates in the United States. Women with a previous early spontaneous preterm birth are at highest risk for recurrence. Weekly intramuscular 17-alpha hydroxyprogesterone caproate reduces the risk of recurrent prematurity. Although current guidelines recommend 17-alpha hydroxyprogesterone caproate initiation between 16 and 20 weeks, in clinical practice, 17-alpha hydroxyprogesterone caproate is started across a spectrum of gestational ages. OBJECTIVE: The objective of the study was to examine the relationship between the gestational age at 17-alpha hydroxyprogesterone caproate initiation and recurrent preterm birth among women with a prior spontaneous preterm birth 16-28 weeks' gestation. STUDY DESIGN: This was a retrospective cohort study of women from a single tertiary care center, 2005-2016. All women with ≥1 singleton preterm births because of a spontaneous onset of contractions, preterm prelabor rupture of membranes, or painless cervical dilation between 16 and 28 weeks followed by a subsequent singleton pregnancy treated with 17-alpha hydroxyprogesterone caproate were included. Women were grouped based on quartiles of gestational age of 17-alpha hydroxyprogesterone caproate initiation (quartile 1, 140/7 to 161/7; quartile 2, 162/7 to 170/7; quartile 3, 171/7 to 186/7; and quartile 4, 190/7 to 275/7). Women with a gestational age of 17-alpha hydroxyprogesterone caproate initiation in quartiles 1 and 2 were considered to have early-start 17-alpha hydroxyprogesterone caproate; those in quartiles 3 and 4 were considered to have late-start 17-alpha hydroxyprogesterone caproate. The primary outcome was recurrent preterm birth <37 weeks' gestation. Secondary outcomes included recurrent preterm birth <34 and <28 weeks' gestation and composite major neonatal morbidity (diagnosis of grade III or IV intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, necrotizing enterocolitis stage II or III, or death). Gestational age at delivery was compared by quartile of 17-alpha hydroxyprogesterone caproate initiation using Kaplan-Meier survival curves and the log-rank test. Logistic regression models estimated odds ratios for the association between gestational age at 17-alpha hydroxyprogesterone caproate initiation and preterm birth <37 weeks' gestation, adjusting for demographics, prior pregnancy and antenatal characteristics. RESULTS: A total of 132 women met inclusion criteria; 52 (39.6%) experienced recurrent preterm birth <37 weeks in the studied pregnancy. 17-Alpha hydroxyprogesterone caproate was initiated at a mean 176/7 ± 2.5 weeks. Demographic and baseline characteristics were similar between women with early-start 17-alpha hydroxyprogesterone caproate (quartiles 1 and 2) compared with those with late-start 17-alpha hydroxyprogesterone caproate (quartiles 3 and 4). Women with early-start 17-alpha hydroxyprogesterone caproate trended toward lower rates of recurrent preterm birth <37 weeks compared with those with late-start 17-alpha hydroxyprogesterone caproate (41.3% vs 57.7%, P = .065). Delivery gestational age was inversely proportional to gestational age at 17-alpha hydroxyprogesterone caproate initiation (quartile 1, 374/7 weeks vs quartile 2, 365/7 vs quartile 3, 361/7 weeks vs quartile 4, 340/7, P = .007). In Kaplan-Meier survival analyses, these differences in delivery gestational age by 17-alpha hydroxyprogesterone caproate initiation quartile persisted across pregnancy (log-rank P < .001). In regression models, later initiation of 17-alpha hydroxyprogesterone caproate was significantly associated with increased odds of preterm birth <37 weeks. Women with early 17-alpha hydroxyprogesterone caproate initiation also had lower rates of major neonatal morbidity than those with later 17-alpha hydroxyprogesterone caproate initiation (1.5% vs 14.3%, P = .005). CONCLUSION: Rates of recurrent preterm birth among women with a prior spontaneous preterm birth 16-28 weeks are high. Women beginning 17-alpha hydroxyprogesterone caproate early deliver later and have improved neonatal outcomes. Clinicians should make every effort to facilitate 17-alpha hydroxyprogesterone caproate initiation at 16 weeks.

Parity and Components of the Metabolic Syndrome Among US Hispanic/Latina Women: Results From the Hispanic Community Health Study/Study of Latinos.

BACKGROUND: Physiological adaptations occurring across successive pregnancies may increase the risk of adverse cardiovascular health outcomes in later life. METHODS AND RESULTS: The association between parity and metabolic syndrome was examined among 7467 Hispanic/Latina women of diverse backgrounds, aged 18 to 74 years, who participated in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) from 2008 to 2011. Metabolic syndrome components were defined according to American Heart Association/National Heart, Lung, and Blood Institute criteria and included abdominal obesity, elevated triglycerides, low high-density lipoprotein cholesterol, high blood pressure, and elevated fasting glucose. Logistic regression models estimated odds ratios (ORs) adjusting for sociodemographic, behavioral, and reproductive characteristics. At HCHS/SOL baseline, women reported none (21.1%), 1 (19.9%), 2 (25.7%), 3 (18.6%), 4 (8.8%), and ≥ 5 (5.9%) live births. When compared with women with 1 birth, those with 4 births had the highest odds of abdominal obesity (OR, 2.0; 95% confidence interval, 1.5-2.8) and overall metabolic syndrome (OR, 1.4; 95% confidence interval, 1.0-2.0) and those with ≥ 5 births had the highest odds of low high-density lipoprotein cholesterol (OR, 1.5; 95% confidence interval, 1.2-2.0) and elevated fasting glucose (OR, 1.6; 95% confidence interval, 1.1-2.4), after adjusting for age, background, education, marital status, income, nativity, smoking, physical activity, menopause, oral contraceptive use, hormone therapy, and field center. Further adjustment for percent body fat attenuated these associations. No associations were observed between parity and elevated triglycerides or high blood pressure. CONCLUSIONS: Higher parity is associated with an increased prevalence of selected components of the metabolic syndrome among Hispanic/Latina women in the US. High parity among Hispanics/Latinas with a high prevalence of abdominal obesity suggests high risk for metabolic dysregulation.

Perceived stress, reproductive hormones, and ovulatory function: a prospective cohort study.

BACKGROUND: Stress has been shown to suppress ovulation in experimental models, but its effect on human reproduction at the population level is unclear. METHODS: Healthy women (n = 259), aged 18-44 years from Western New York, were followed for 2 menstrual cycles (2005-2007). Women completed daily perceived stress assessments, a 4-item Perceived Stress Scale (PSS-4) up to 4 times each cycle, and a 14-item PSS at baseline. Mixed model analyses were used to assess effects of stress on log reproductive hormone concentrations and sporadic anovulation. RESULTS: High versus low daily stress was associated with lower estradiol (-9.5% [95% confidence interval (CI) = -15.6% to -3.0%]), free estradiol (-10.4% [-16.5% to -3.9%]), and luteinizing hormone (-14.8% [-21.3% to -7.7%]) and higher follicle-stimulating hormone (6.2% [95% CI = 2.0% to 10.5%]) after adjusting for age, race, percent body fat, depression score, and time-varying hormones and vigorous exercise. High versus low daily stress was also associated with lower luteal progesterone (-10.4% [95% CI = -19.7% to -0.10%]) and higher odds of anovulation (adjusted odds ratio = 2.2 [95% CI = 1.0 to 4.7]). For each unit increase in daily stress level, women had a 70% higher odds of an anovulatory episode (odds ratio = 1.7 [1.1 to 2.4]). Similar but attenuated results were found for the association between the PSS-4 and reproductive hormones, while null findings were found for the baseline PSS. CONCLUSION: Daily perceived stress does appear to interfere with menstrual cycle function among women with no known reproductive disorders, warranting further research to explore potential population-level impacts and causal biologic mechanisms.

Correlates of Self-Reported Physical Activity at 3 and 12 Months Postpartum.

BACKGROUND: Postpartum women are encouraged to participate in ≥ 150 min/week of moderate-intensity aerobic activity, but few women achieve this recommendation. This study sought to identify factors associated with participation in physical activity after pregnancy. METHODS: We examined correlates of any self-reported moderate-to-vigorous physical activity (MVPA) (≥ 10 min/week across all modes) and any recreational MVPA (≥ 10 min/week) among women enrolled in the Pregnancy, Infection, and Nutrition Postpartum study at 3 months postpartum (n = 667) and at 12 months postpartum (n = 530). Potential correlates were identified according to the socioecological framework. RESULTS: At 3 and 12 months postpartum, lower odds of participation in any MVPA were associated with lower education, breastfeeding, and minimal emotional support. Low exercise self-efficacy, receipt of advice about physical activity, and warmer seasons were associated with higher odds of any MVPA. For recreational MVPA, lower odds of participation were associated with unmarried status, lower education, employment, low income, preeclampsia, and minimal emotional support. Involvement in child/adult care activities, transportation MVPA, and warmer seasons were associated with higher odds of recreational MVPA. CONCLUSION: These findings suggest that several modifiable intrapersonal and interpersonal factors are associated with postpartum MVPA and should be considered when developing interventions to help women maintain or increase MVPA after pregnancy.

The association between physical activity and maternal sleep during the postpartum period.

Physical activity is associated with improved sleep quality and duration in the general population, but its effect on sleep in postpartum women is unknown. We examined cross-sectional and longitudinal associations between hours/week of self-reported domain-specific and overall moderate to vigorous physical activity (MVPA) and sleep quality and duration at 3- and 12-months postpartum among a cohort of 530 women in the Pregnancy, Infection, and Nutrition Postpartum Study. MVPA was not associated with sleep quality or duration at 3-months postpartum. At 12-months postpartum, a 1 h/week increase in recreational MVPA was associated with higher odds of good (vs. poor) sleep quality (odds ratio, OR 1.14; 95 % confidence interval, CI, 1.03-1.27) and a 1 h/week increase in child/adult care MVPA was associated with lower odds of good (vs. poor) sleep quality (OR = 0.93; 95 % CI 0.88-0.99). A 1 h/week increase in child/adult care MVPA (OR 1.08, 95 % CI 1.00-1.16) was associated with higher odds of long sleep duration and 1 h/week increases in indoor household (OR 1.09, 95 % CI 1.01-1.18) and overall MVPA (OR 1.04, 95 % CI 1.01-1.07) were associated with higher odds of short (vs. normal) sleep duration. Comparing 3-months postpartum to 12-months postpartum, increased work MVPA was associated with good sleep quality (OR 2.40, 95 % CI 1.12-5.15) and increased indoor household MVPA was associated with short sleep duration (OR 1.85, 95 % CI 1.05-3.27) as measured at 12-months postpartum. Selected domains of MVPA and their longitudinal increases were associated with sleep quality and duration at 12-months postpartum. Additional research is needed to elucidate whether physical activity can improve postpartum sleep.

The effect of physical activity across the menstrual cycle on reproductive function.

PURPOSE: To evaluate the association between physical activity (PA) across the menstrual cycle and reproductive function. METHODS: The BioCycle Study (2005-2007) followed 259 healthy premenopausal women not using hormonal contraceptives for up to two menstrual cycles (N = 509 cycles). Serum leptin, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and testosterone were measured five to eight times per cycle. Linear mixed models were used to estimate the effect of past-week PA (measured four times during each cycle) on hormone levels. Past-week PA was categorized into tertiles based on metabolic equivalent of task hours per week (cut-points were 15.3 and 35.7). Risk ratios for sporadic anovulation were estimated using generalized linear models. Analyses adjusted for habitual PA (assessed at baseline), body mass index, race, age, and perceived stress. Linear mixed models used inverse probability weights to control for concurrent reproductive hormones and caloric intake. RESULTS: High past-week PA was inversely associated with leptin (-6.6%; 95% confidence interval, -10.6 to -2.5) and luteal phase progesterone (-22.1%; -36.2 to -4.7) as compared with low past-week PA. High past-week PA was not significantly associated with sporadic anovulation (adjusted risk ratio, 1.5; 0.6 to 3.4). CONCLUSIONS: High levels of PA were modestly associated with changes in select hormones but not sporadic anovulation among moderate to highly active premenopausal women.

Pregnant driver-associated motor vehicle crashes in North Carolina, 2001-2008.

BACKGROUND: Motor vehicle crashes are the leading cause of maternal injury-related mortality during pregnancy in the United States, yet pregnant women remain an understudied population in motor vehicle safety research. METHODS: We estimated the risk of being a pregnant driver in a crash among 878,546 pregnant women, 16-46 years, who reached the 20th week of pregnancy in North Carolina (NC) from 2001 to 2008. We also examined the circumstances surrounding the crash events. Pregnant drivers in crashes were identified by probabilistic linkage of live birth and fetal death records and state motor vehicle crash reports. RESULTS: During the 8-year study period, the estimated risk of being a driver in a crash was 12.6 per 1000 pregnant women. Pregnant women at highest risk of being drivers in serious crashes were 18-24 years old (4.5 per 1000; 95% confidence interval, CI,4.3, 4.7), non-Hispanic black (4.8 per 1000; 95% CI=4.5, 5.1), had high school diplomas only (4.5 per 1000; 95% CI=4.2, 4.7) or some college (4.1 per 1000; 95% CI=3.9, 4.4), were unmarried (4.7 per 1000; 95% CI=4.4, 4.9), or tobacco users (4.5 per 1000; 95% CI=4.1, 5.0). A high proportion of crashes occurred between 20 and 27 weeks of pregnancy (45%) and a lower proportion of crashes involved unbelted pregnant drivers (1%) or airbag deployment (10%). Forty percent of crashes resulted in driver injuries. CONCLUSIONS: NC has a relatively high pregnant driver crash risk among the four U.S. states that have linked vital records and crash reports to examine pregnancy-associated crashes. Crash risks were especially elevated among pregnant women who were young, non-Hispanic black, unmarried, or used tobacco. Additional research is needed to quantify pregnant women's driving frequency and patterns.

Physical activity and injuries during pregnancy.

BACKGROUND: Although physical activity can provide health benefits to pregnant women, population-based research on the circumstances surrounding injuries from physical activity during pregnancy is lacking. METHODS: Physical activity and subsequent injuries among a cohort of 1469 pregnant women in North Carolina were examined prospectively from the third phase of the Pregnancy, Infection, and Nutrition Study between 2001 and 2005. Chi-square analyses were used to compare distributions of maternal characteristics among women who sustained injuries from physical activity and women who reported no injuries during pregnancy. Injury incidence rates were calculated. RESULTS: Few pregnant women (N = 34) reported a physical activity-related injury during pregnancy. The rates of physical activity-related and exercise-related injuries during pregnancy were 3.2 per 1000 physical activity hours and 4.1 per 1000 exercise hours, respectively. The most common types of injuries were bruises or scrapes (55%). Among all injuries, 33% resulted from exercise and 67% resulted from nonexercise physical activities. Sixty-four percent of all injuries were due to falls. CONCLUSIONS: The incidence of injury from physical activity was low during pregnancy. Women should continue to be encouraged to maintain involvement in physical activity during pregnancy, while being aware of the potential for injury, particularly falls, from these activities.