Prior Term Birth Decreases the Risk of Preterm Birth in a Subsequent Twin Gestation.

OBJECTIVE: The aim of the study is to examine the association between the risk of preterm delivery among women with twin pregnancies and their obstetric history. STUDY DESIGN: We designed a retrospective cohort study of live twin births in 2008 in the United States that delivered after 240/7 weeks. Women were categorized into nulliparas, multiparas with prior term delivery, and multiparas with prior preterm delivery. The incidence of preterm birth was compared using Chi-square test and multivariable logistic regression models. RESULTS: A total of 32,895 nulliparous and 64,701 multiparous women with twin pregnancies were included in the study. Of the multiparous women, 2,505 (4%) had a history of a prior preterm delivery. Multiparous women with prior term birth were more likely to deliver at term (: 43%): in the index twin pregnancy than nulliparous women (40%) and multiparous women with a prior preterm birth (21%; p < 0.001). Compared with nulliparous women, prior term birth was protective against preterm delivery (adjusted odds ratio [aOR] = 0.67 [95% confidence interval: 0.60-0.74] for delivery <28 weeks and aOR = 0.79 [0.71-0.77] for delivery <34 weeks). CONCLUSION: Among multiparous women with twins, a prior term delivery appeared to be protective against preterm delivery compared with nulliparous women with twins. KEY POINTS: · Prior term birth is protective against preterm birth in subsequent twin pregnancy.. · A prior term birth confers an OR of 0.66 for delivery prior to 28 weeks in twin pregnancies.. · A prior preterm birth renders a twin pregnancy nearly twice as likely to deliver before 28 weeks..

Disparities in Trial of Labor among Women with Twin Gestations in the United States.

OBJECTIVE: The aim of the study is to examine clinical and demographic factors associated with trial of labor (TOL) among women with twin gestations eligible for a vaginal delivery. STUDY DESIGN: This was a population-based cohort study of women giving birth to twin gestations in the United States (2012-2014). Inclusion criteria for the analysis included live births greater than 23 weeks' gestation and a cephalic presenting twin. Women with prior cesarean delivery were excluded. Women were categorized by whether they underwent a TOL. Clinical and demographic characteristics associated with TOL status were evaluated using multivariable logistic regression analyses. Secondary analyses with stratification by parity and by second twin presentation were performed. RESULTS: Of 90,000 women eligible for inclusion, a minority (39.3%) underwent TOL. Women who had a greater gestational age at delivery were more likely to have a TOL. In contrast, several demographic factors were associated with decreased likelihood of TOL, including maternal age >35 years and identifying as Hispanic or Asian compared with non-Hispanic White. No differences in odds of TOL were observed for women who were identified as non-Hispanic Black versus non-Hispanic White, nor were other demographic factors such as marital status, insurance status, or educational attainment associated with undergoing TOL. Clinical factors associated with decreased odds of TOL included nulliparity, obesity, and hypertensive disorders of pregnancy. Results did not substantively change when stratified by parity or second twin presentation, nor did findings differ in the subgroup who delivered at 32 weeks of gestation or greater. CONCLUSION: In this large population of women with twins who were eligible for a TOL, a minority of individuals attempted a vaginal delivery. Demographic and clinical factors such as older maternal age, Asian or Hispanic racial or ethnic identification, nulliparity, and obesity are associated with decreased odds of undergoing TOL. KEY POINTS: · Understanding disparities in trial of labor among patients with twins is key to promoting equity.. · Older maternal age and identifying as Hispanic or Asian were associated with lower odds of TOL.. · Nulliparity, obesity, and hypertension were associated with decreased odds of TOL..

Perinatal Outcomes of Twin Gestations with and without Gestational Diabetes Mellitus.

OBJECTIVE: Existing data suggest that obstetric outcomes for individuals with twin gestations, who have gestational diabetes mellitus (GDM), may be comparable to those who do not have GDM, yet studies are limited by small sample sizes. The aim of this study was to examine differences in maternal and neonatal outcomes of individuals with twin gestations based on presence of GDM. METHODS: This was a population-based retrospective cohort study of individuals giving birth to twins in the United States between 2012 and 2014. Inclusion criteria were live births (≥24 weeks) and available information on GDM status; individuals with pregestational diabetes were excluded. Participants were categorized as either having had or not had GDM. Multivariable logistic regression was utilized to assess the independent association of GDM with adverse maternal outcomes, whereas generalized estimating equation models were used to estimate associations with neonatal outcomes to account for clustering. RESULTS: Of 173,196 individuals meeting inclusion criteria, 13,194 (7.6%) had GDM. Individuals with GDM were more likely to be older, identify as Hispanic or Asian race and ethnicity, married, college educated, privately insured, and obese than those without GDM. After adjusting for potential confounding variables, those with GDM were more likely to have hypertensive disorders (18.0 vs. 10.2%) and undergo cesarean delivery (51.2 vs. 47.3%). Neonates born to individuals with GDM were more likely to require mechanical ventilation for greater than 6 hours (6.5 vs. 5.6%) and experience neonatal intensive care unit (NICU) admission (41.1 vs. 36.2%), but were less likely to be low birth weight or have small for gestational age status (16.2 vs. 19.5%). Findings were confirmed in a sensitivity analysis of neonates born at 32 weeks of gestation or greater. CONCLUSION: Odds of poor obstetric and neonatal outcomes are increased for individuals with twin gestations complicated by GDM. KEY POINTS: · Individuals with GDM and twin gestation have higher odds of developing hypertensive disorders during pregnancy and of undergoing cesarean delivery.. · Neonates of such pregnancies are less likely to be low birth weight or small for gestational age.. · Neonates of pregnancies complicated by GDM and twin gestation are more likely to require mechanical ventilation and experience NICU admission..

Association between the Degree of Twin Birthweight Discordance and Perinatal Outcomes.

BACKGROUND: Twin birthweight discordance is associated with adverse outcomes. OBJECTIVE: To determine what degree of twin birthweight discordance is associated with adverse outcomes. STUDY DESIGN: This is a retrospective cohort study of twins with vertex twin A delivered vaginally at 36 to 40 weeks (U.S. Vital Statistics Natality birth certificate registry data 2012-2014). The primary outcome was a composite of neonatal morbidity: 5-minute Apgar < 7, neonatal intensive care unit admission, neonatal mechanical ventilation > 6 hours, neonatal seizure, and/or neonatal transport to a higher level of care. Effect estimates were expressed as incidence rate and adjusted odds ratio (aOR) controlling for confounding using multivariate clustered analysis for between-pair effects, and multilevel random effect generalized estimating equation regressions to account for within-pair effects. We adjusted for sex discordance, breech delivery of the second twin, maternal race/ethnicity, nulliparity, age, marital status, obesity, and socioeconomic status. RESULTS: In comparison to birthweight discordance of ≤20%, aORs with 95% confidence intervals (CIs) by weight discordance of the primary outcome among 27,276 twin deliveries were as follows: 20.01 to 25% (aOR: 1.46 [95% CI: 1.29-1.65]); 25.01 to 30% (aOR: 1.96 [95% CI: 1.68-2.29]); and 30.01 to 60% (aOR: 2.97 [95% CI: 2.52-3.50]). CONCLUSION: Twin birthweight discordance >20% was associated with increased odds of adverse neonatal outcome.

Gestational Weight Gain during Pregnancy as an Important Factor Influencing a Successful Trial of Labor following Two Previous Cesareans.

OBJECTIVE: We sought to identify factors associated with a successful trial of labor (TOL) following two cesarean deliveries (CDs) in a contemporary North American cohort. STUDY DESIGN: This is a retrospective cohort study of term, nonanomalous, singleton, vertex pregnancies attempting a vaginal birth after cesarean (VBAC) following a history of two previous CDs in the United States from 2012 to 2014. Maternal and intrapartum factors were analyzed using chi-square tests and multivariable logistic regression. RESULTS: A total of 22,762 women met the inclusion criteria and underwent TOL. Of these, 12,192 (53.6%) had a VBAC. Using multivariate logistic regression, previous vaginal delivery and delivery at 40 to 41 weeks' gestation were associated with VBAC; maternal age, education, Medicaid insurance, non-Caucasian race/ethnicity, weight (overweight or obese), and gestational weight gain above the Institute of Medicine guidelines (adjusted odds ratio: 0.88; 95% confidence interval: 0.81-0.95) were associated with CD. Induction of labor did not affect the VBAC rate. CONCLUSION: For those desiring a TOL after two previous CDs, prospective studies are needed to assess interventions that limit gestational weight gain as well as the safety and optimal timing of an induction of labor. The decision to attempt a TOL should be guided by counseling regarding the risks, benefits, and chances of a successful TOL.

Planned Out-of-Hospital Birth and Birth Outcomes.

BACKGROUND: The frequency of planned out-of-hospital birth in the United States has increased in recent years. The value of studies assessing the perinatal risks of planned out-of-hospital birth versus hospital birth has been limited by cases in which transfer to a hospital is required and a birth that was initially planned as an out-of-hospital birth is misclassified as a hospital birth. METHODS: We performed a population-based, retrospective cohort study of all births that occurred in Oregon during 2012 and 2013 using data from newly revised Oregon birth certificates that allowed for the disaggregation of hospital births into the categories of planned in-hospital births and planned out-of-hospital births that took place in the hospital after a woman's intrapartum transfer to the hospital. We assessed perinatal morbidity and mortality, maternal morbidity, and obstetrical procedures according to the planned birth setting (out of hospital vs. hospital). RESULTS: Planned out-of-hospital birth was associated with a higher rate of perinatal death than was planned in-hospital birth (3.9 vs. 1.8 deaths per 1000 deliveries, P=0.003; odds ratio after adjustment for maternal characteristics and medical conditions, 2.43; 95% confidence interval [CI], 1.37 to 4.30; adjusted risk difference, 1.52 deaths per 1000 births; 95% CI, 0.51 to 2.54). The odds for neonatal seizure were higher and the odds for admission to a neonatal intensive care unit lower with planned out-of-hospital births than with planned in-hospital birth. Planned out-of-hospital birth was also strongly associated with unassisted vaginal delivery (93.8%, vs. 71.9% with planned in-hospital births; P<0.001) and with decreased odds for obstetrical procedures. CONCLUSIONS: Perinatal mortality was higher with planned out-of-hospital birth than with planned in-hospital birth, but the absolute risk of death was low in both settings. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development.).

Association between gestational weight gain and perinatal outcomes in women with chronic hypertension.

BACKGROUND: Gestational weight gain above or below the 2009 National Academy of Medicine guidelines has been associated with adverse maternal and neonatal outcomes. Although it has been well established that excess gestational weight gain is associated with the development of gestational hypertension and preeclampsia, the relationship between gestational weight gain and adverse perinatal outcomes among women with pregestational (chronic) hypertension is less clear. OBJECTIVE: The objective of this study was to examine the relationship between gestational weight gain above and below National Academy of Medicine guidelines and perinatal outcomes in a large, population-based cohort of women with chronic hypertension. STUDY DESIGN: This is a population-based retrospective cohort study of women with chronic hypertension who had term, singleton, vertex births in the United States from 2012 through 2014. Prepregnancy body mass index was calculated using self-reported prepregnancy weight and height. Women were categorized into 4 groups based on gestational weight gain and prepregnancy body mass index: (1) weight gain less than, (2) weight gain within, (3) weight gain 1-19 lb in excess of, and (4) weight gain ≥20 lb in excess of the National Academy of Medicine guidelines. The χ2 tests and multivariable logistic regression analysis were used for statistical comparisons. Stratified analyses by body mass index category were additionally performed. RESULTS: In this large birth cohort, 101,259 women met criteria for inclusion. Compared to hypertensive women who had gestational weight gain within guidelines, hypertensive women with weight gain ≥20 lb over National Academy of Medicine guidelines were more likely to have eclampsia (adjusted odds ratio, 1.93; 95% confidence interval, 1.54-2.42) and cesarean delivery (adjusted odds ratio, 1.60; 95% confidence interval, 1.50-1.70). Excess weight gain ≥20 lb over National Academy of Medicine guidelines was also associated with increased odds of 5-minute Apgar <7 (adjusted odds ratio, 1.29; 95% confidence interval, 1.13-1.47), neonatal intensive care unit admission (adjusted odds ratio, 1.23; 95% confidence interval, 1.14-1.33), and large-for-gestational-age neonates (adjusted odds ratio, 2.41; 95% confidence interval, 2.27-2.56) as well as decreased odds of small-for-gestational-age status (adjusted odds ratio, 0.52; 95% confidence interval, 0.46-0.58). Weight gain 1-19 lb over guidelines was associated with similar fetal growth outcomes although with a smaller effect size. In contrast, weight gain less than National Academy of Medicine guidelines was not associated with adverse maternal outcomes but was associated with increased odds of small for gestational age (adjusted odds ratio, 1.31; 95% confidence interval, 1.21-1.52) and decreased odds of large-for-gestational-age status (adjusted odds ratio, 0.86; 95% confidence interval, 0.81-0.92). Analysis of maternal and neonatal outcomes stratified by body mass index demonstrated similar findings. CONCLUSION: Women with chronic hypertension who gain less weight than National Academy of Medicine guidelines experience increased odds of small-for-gestational-age neonates, whereas excess weight gain ≥20 lb over National Academy of Medicine guidelines is associated with cesarean delivery, eclampsia, 5-minute Apgar <7, neonatal intensive care unit admission, and large-for-gestational-age neonates.

Duration of Second Stage of Labour at Term and Pushing Time: Risk Factors for Postpartum Haemorrhage.

BACKGROUND: Prolonged labour is associated with increased risk of postpartum haemorrhage (PPH), but the role of active pushing time and the relation with management during labour remains poorly understood. METHODS: A population-based cohort study from electronic medical record data in the Stockholm-Gotland Region, Sweden. We included 57 267 primiparous women with singleton, term gestation, livebirths delivered vaginally in cephalic presentation in 2008-14. We performed multivariable Poisson regression to estimate the association between length of second stage, pushing time, and PPH (estimated blood loss >500 mL during delivery), adjusting for maternal, delivery, and fetal characteristics as potential confounders. RESULTS: The incidence of PPH was 28.9%. The risk of PPH increased with each passing hour of second stage: compared with a second stage <1 h, the adjusted relative risk (RR) for PPH were for 1 to <2 h 1.10 (95% confidence interval (CI) 1.07, 1.14); for 2 to <3 h 1.15 (95% CI 1.10, 1.20); for 3 to <4 h 1.28 (95% CI 1.22, 1.33); and for ≥4 h 1.40 (95% CI 1.33, 1.46). PPH also increased with pushing time exceeding 30 min. Compared to pushing time between 15 and 29 min, the RR for PPH were for <15 min 0.98 (95% CI 0.94, 1.03); for 30-44 min 1.08 (95% CI 1.04, 1.12); for 45-59 min 1.11 (95% CI 1.06, 1.16); and for ≥60 min 1.20 (95% CI 1.15, 1.25). CONCLUSIONS: Increased length of second stage and pushing time during labour are both associated with increased risk of PPH.

Risk factors for brachial plexus injury in a large cohort with shoulder dystocia.

OBJECTIVE: To examine birthweight and other predictors of brachial plexus injury (BPI) among births complicated by shoulder dystocia. STUDY DESIGN: A retrospective cohort study of term births complicated by shoulder dystocia in California between 1997 and 2006. Birthweight at time of delivery was stratified into 500-g intervals. Women were further stratified by diabetes status, parity, and race/ethnicity. The perinatal outcome of BPI was assessed. RESULTS: This study included 62,762 deliveries complicated by shoulder dystocia, of which 3168 (5 %) resulted in BPI. The association between birthweight and BPI remained significant regardless of confounders. Each increasing birthweight interval was associated with an increasing risk of BPI compared with 3000-3499-g birthweight. Race/ethnicity, diabetes, and parity were also independently associated with BPI. CONCLUSION: Increasing birthweight increases the risk of BPI among births with shoulder dystocia, independent of advanced maternal age, race, parity, gestational diabetes, or operative vaginal delivery.

The impact of hospital obstetric volume on maternal outcomes in term, non-low-birthweight pregnancies.

OBJECTIVE: The impact of hospital obstetric volume specifically on maternal outcomes remains under studied. We examined the impact of hospital obstetric volume on maternal outcomes in low-risk women who delivered non-low-birthweight infants at term. STUDY DESIGN: We conducted a retrospective cohort study of term singleton, non-low-birthweight live births from 2007-2008 in California. Deliveries were categorized by hospital obstetric volume categories and separately for nonrural hospitals (category 1: 50-1199 deliveries per year; category 2: 1200-2399; category 3: 2400-3599, and category 4: ≥3600) and rural hospitals (category R1: 50-599 births per year; category R2: 600-1699; category R3: ≥1700). Maternal outcomes were compared with the use of the chi-square test and multivariable logistic regression. RESULTS: There were 736,643 births in 267 hospitals that met study criteria. After adjustment for confounders, there were higher rates of postpartum hemorrhage in the lowest-volume rural hospitals (category R1 adjusted odds ratio, 3.06; 95% confidence interval, 1.51-6.23). Rates of chorioamnionitis, endometritis, severe perineal lacerations, and wound infection did not differ between volume categories. Longer lengths of stay were observed after maternal complications (eg, chorioamnionitis) in the lowest-volume hospitals (16.9% prolonged length of stay in category 1 hospitals vs 10.5% in category 4 hospitals; adjusted odds ratio, 1.91; 95% confidence interval, 1.01-3.61). CONCLUSION: After confounder adjustment, few maternal outcomes differed by hospital obstetric volume. However, elevated odds of postpartum hemorrhage in low-volume rural hospitals raises the possibility that maternal outcomes may differ by hospital volume and geography. Further research is needed on maternal outcomes in hospitals of different obstetric volumes.

Weight gain in pregnancy: does the Institute of Medicine have it right?

OBJECTIVE: We aimed to examine whether women who adhered to Institute of Medicine (IOM) guidelines for gestational weight gain (GWG) had improved perinatal outcomes. STUDY DESIGN: This is a population-based retrospective cohort study of nulliparous women with term singleton vertex births in the United States from 2011 through 2012. Women with medical or obstetric complications were excluded. Prepregnancy body mass index was calculated using reported weight and height. Women were categorized into 4 groups based on GWG and prepregnancy body mass index: (1) weight gain less than, (2) weight gain within, (3) weight gain 1-19 lb in excess of, and (4) weight gain ≥20 lb in excess of the IOM guidelines. The χ(2) test and multivariable logistic regression analysis were used for statistical comparisons. RESULTS: Compared to women who had GWG within the IOM guidelines, women with excessive weight gain, particularly ≥20 lb, were more likely to have adverse maternal outcomes (preeclampsia: adjusted odds ratio [aOR], 2.78; 95% confidence interval [CI], 2.82-2.93; eclampsia: aOR, 2.51; 95% CI, 2.27-2.78; cesarean: aOR, 2.1; 95% CI, 2.14-2.19), blood transfusion (aOR, 1.22; 95% CI, 1.11-1.33), and neonatal outcomes (5-minute Apgar <4: aOR, 1.22; 95% CI, 1.14-1.31; ventilation use >6 hours: aOR, 1.24; 95% CI, 1.15-1.33; seizure: aOR, 1.53; 95% CI, 1.24-1.89). Women who gained less than IOM guidelines had lower risks of hypertensive disorders of pregnancy and obstetric interventions but were more likely to have small-for-gestational-age neonates (aOR, 1.55; 95% CI, 1.52-1.59). CONCLUSION: Women whose GWG is in excess of IOM guidelines have higher risk of adverse maternal and neonatal outcomes, particularly in women with ≥20 lb excess weight gain above guidelines while women who had weight gain below the IOM guidelines were less likely to have maternal morbidity but had higher odds of small for gestational age.

The risk of fetal death in nonanomalous pregnancies affected by polyhydramnios.

OBJECTIVE: The objective of the study was to evaluate the ongoing risk of intrauterine fetal demise (IUFD) in nonanomalous pregnancies affected by polyhydramnios. STUDY DESIGN: We analyzed a retrospective cohort of all singleton, nonanomalous births in California between 2005 and 2008 as recorded in a statewide birth certificate registry. We included all births between 24+0 and 41+6 weeks' gestational age, excluding multiple gestations, major congenital anomalies, and pregnancies affected by oligohydramnios. Polyhydramnios was identified by International Classification of Diseases, ninth revision, codes. χ(2) tests were used to compare the dichotomous outcomes, and multivariable logistic regression analyses were then performed to control for potential confounders. We analyzed the data for pregnancies affected and unaffected by polyhydramnios. The IUFD risk was expressed as a rate per 10,000. RESULTS: The risk of IUFD in pregnancies affected by polyhydramnios was greater at every gestational age compared with unaffected pregnancies. The IUFD risk in pregnancies affected by polyhydramnios was more than 7 times higher than unaffected pregnancies at 37 weeks at a rate of 18.0 (95% confidence interval [CI], 9.0-32.6) vs 2.4 (95% CI, 2.0-2.5) and was 11-fold higher by 40 weeks' gestational age at a rate of 66.3 (95% CI, 10.8-68.6) vs 6.0 (95% CI, 5.1-6.3) in unaffected pregnancies. When adjusted for multiple confounding variables, the presence of polyhydramnios remained associated with an increased odds of IUFD in nonanomalous singleton pregnancies, with an adjusted odds ratio of 5.5 (95% CI, 4.1-7.6). CONCLUSION: Ongoing risk of IUFD is greater in low-risk pregnancies affected by polyhydramnios at all gestational ages compared with unaffected pregnancies with the greatest increase in risk at term. Although further study is needed to explore the underlying etiology of polyhydramnios in these cases, the identification of polyhydramnios alone may warrant increased antenatal surveillance.

Second stage of labor.

Current American College of Obstetricians and Gynecologists' definition of prolonged second stage diagnoses 10% to 14% of nulliparous and 3% to 3.5% of multiparous women as having a prolonged second stage. The progression of labor in modern obstetrics may have deviated from the current labor norms established in the 1950s, likely due to differences in obstetric population characteristics and variation in clinical practice. Optimal management of the second stage in women with and without epidural remains debatable. Although prolonged second stage is associated with increased risk of maternal morbidity, conflicting data exist regarding the duration of second stage and associated neonatal morbidity and mortality.

Fetal malposition: impact and management.

Fetal malposition, either occiput posterior or transverse (OT), leads to greater risk of cesarean delivery, prolonged labor, and increased perinatal morbidity. Historically, there is a known association between epidural use and malposition that was assumed to be due to the increased discomfort of laboring with a fetus in the occiput posterior position. However, evidence now suggests that the epidural itself may contribute to fetal malposition by impacting the probability of internal rotation. Fetal malposition may be impacted by manual rotation. Manual rotation has been associated with greater rates of delivering in the occiput anterior position and lower rates of cesarean delivery.

The mortality risk of expectant management compared with delivery stratified by gestational age and race and ethnicity.

OBJECTIVE: The objective of the study was to compare the mortality risk of expectant management with the risk of delivery at each week of term pregnancy in 4 racial/ethnic groups. STUDY DESIGN: This was a retrospective cohort study of all nonanomalous, term deliveries in California from 1997 to 2006 among white, black, Hispanic, and Asian women. In each racial/ethnic group, we compared the risk of infant death at each week with a composite risk representing the mortality risk of 1 week of expectant management. RESULTS: The risk of stillbirth and infant death is highest in black women (stillbirth risk: 18.0 per 10,000, infant death: 24.4 per 10,000, compared with 9.4 per 10,000 and 10.8 per 10,000 in white women, respectively; P < .001). Although absolute risks differ by race/ethnicity, the composite risk of expectant management does not surpass the risk of delivery until 39 weeks in any group. At 39 weeks these absolute risk differences are low, however, with a number needed to deliver to prevent 1 death ranging from 751 (among black women) to 2587 (among Asian women). CONCLUSION: The mortality risk of expectant management exceeds the risk of delivery at 39 weeks in all racial/ethnic groups, despite variation in absolute risks.

What is the optimal gestational age for women with gestational diabetes type A1 to deliver?

OBJECTIVE: Type A1 gestational diabetes mellitus (A1GDM), also known as diet-controlled gestational diabetes, is associated with an increase in adverse perinatal outcomes such as macrosomia and Erb palsy. However, it remains unclear when to deliver these women because optimal timing of delivery requires balancing neonatal morbidities from early term delivery against the risk of intrauterine fetal demise (IUFD). We sought to determine the optimal gestational age (GA) for women with A1GDM to deliver. STUDY DESIGN: A decision-analytic model was built to compare the outcomes of delivery at 37-41 weeks in a theoretical cohort of 100,000 women with A1GDM. Strategies involving expectant management until a later GA accounted for probabilities of spontaneous delivery, indicated delivery, and IUFD during each week. GA-associated risks of neonatal complications included cerebral palsy, infant death, and Erb palsy. Probabilities were derived from the literature, and total quality-adjusted life years were calculated. Sensitivity analyses were used to investigate the robustness of the baseline assumptions. RESULTS: Our model showed that induction at 38 weeks maximized quality-adjusted life years. Within our cohort, delivery at 38 weeks would prevent 48 stillbirths but lead to 12 more infant deaths compared to 39 weeks. Sensitivity analysis revealed that 38 weeks remains the optimal timing of delivery until IUFD rates fall <0.3-fold of our baseline assumption, at which point expectant management until 39 weeks is optimal. CONCLUSION: By weighing the risks of IUFD against infant deaths and neonatal morbidities from early term delivery, we determined that the ideal GA for women with A1GDM to deliver is 38 weeks.

Economic downturns and male cesarean deliveries: a time-series test of the economic stress hypothesis.

BACKGROUND: In light of the recent Great Recession, increasing attention has focused on the health consequences of economic downturns. The perinatal literature does not converge on whether ambient economic declines threaten the health of cohorts in gestation. We set out to test the economic stress hypothesis that the monthly count of cesarean deliveries (CD), which may gauge the level of fetal distress in a population, rises after the economy declines. We focus on male CD since the literature reports that male more than female fetuses appear sensitive to stressors in utero. METHODS: We tested our ecological hypothesis in California for 228 months from January 1989 to December 2007, the most recent data available to us at the time of our tests. We used as the independent variable the Bureau of Labor Statistics unadjusted total state employment series. Time-series methods controlled for patterns of male CD over time. We also adjusted for the monthly count of female CD, which controls for well-characterized factors (e.g., medical-legal environment, changing risk profile of births) that affect CD but are shared across infant sex. RESULTS: Findings support the economic stress hypothesis in that male CD increases above its expected value one month after employment declines (employment coefficient = -24.09, standard error = 11.88, p = .04). Additional exploratory analyses at the metropolitan level indicate that findings in Los Angeles and Orange Counties appear to drive the State-level relation. CONCLUSIONS: Contracting economies may perturb the health of male more than female fetuses sufficiently enough to warrant more CD. Male relative to female CD may sensitively gauge the cohort health of gestations.

The effect of maternal body mass index on perinatal outcomes in women with diabetes.

OBJECTIVE: To determine the effect of increasing maternal obesity, including superobesity (body mass index [BMI] ≥ 50 kg/m2), on perinatal outcomes in women with diabetes. STUDY DESIGN: Retrospective cohort study of birth records for all live-born nonanomalous singleton infants ≥ 37 weeks' gestation born to Missouri residents with diabetes from 2000 to 2006. Women with either pregestational or gestational diabetes were included. RESULTS: There were 14,595 births to women with diabetes meeting study criteria, including 7,082 women with a BMI > 30 kg/m2 (48.5%). Compared with normal-weight women with diabetes, increasing BMI category, especially superobesity, was associated with a significantly increased risk for preeclampsia (adjusted relative risk [aRR] 3.6, 95% confidence interval [CI] 2.5, 5.2) and macrosomia (aRR 3.0, 95% CI 1.8, 5.40). The majority of nulliparous obese women with diabetes delivered via cesarean including 50.5% of obese, 61.4% of morbidly obese, and 69.8% of superobese women. The incidence of primary elective cesarean among nulliparous women with diabetes increased significantly with increasing maternal BMI with over 33% of morbidly obese and 39% of superobese women with diabetes delivering electively by cesarean. CONCLUSION: Increasing maternal obesity in women with diabetes is significantly associated with higher risks of perinatal complications, especially cesarean delivery.

Maternal diagnosis of obesity and risk of cerebral palsy in the child.

OBJECTIVE: To examine the association between maternal hospital diagnoses of obesity and risk of cerebral palsy (CP) in the child. STUDY DESIGN: For all California hospital births from 1991-2001, we linked infant and maternal hospitalization discharge abstracts to California Department of Developmental Services records of children receiving services for CP. We identified maternal hospital discharge diagnoses of obesity (International Classification of Diseases, 9th edition 646.1, 278.00, or 278.01) and morbid obesity (International Classification of Diseases, 9th edition 278.01), and performed logistic regression to explore the relationship between maternal obesity diagnoses and CP. RESULTS: Among 6.2 million births, 67 200 (1.1%) mothers were diagnosed with obesity, and 7878 (0.1%) with morbid obesity; 8798 (0.14%) children had CP. A maternal diagnosis of obesity (relative risk [RR] 1.30, 95% CI 1.09-1.55) or morbid obesity (RR 2.70, 95% CI 1.89-3.86) was associated with increased risk of CP. In multivariable analysis adjusting for maternal race, age, education, prenatal care, insurance status, and infant sex, both obesity (OR 1.27, 95% CI 1.06-1.52) and morbid obesity (OR 2.56, 95% CI 1.79-3.66) remained independently associated with CP. On stratified analyses, the association of obesity (RR 1.72, 95% CI 1.25-2.35) or morbid obesity (RR 3.79, 95% CI 2.35-6.10) with CP was only significant among women who were hospitalized prior to the birth admission. Adjusting for potential comorbidities and complications of obesity did not eliminate this association. CONCLUSIONS: Maternal obesity may confer an increased risk of CP in some cases. Further studies are needed to confirm this finding.