Postpartum readmission for hypertension and pre-eclampsia: development and validation of a predictive model.

OBJECTIVE: To develop a model for predicting postpartum readmission for hypertension and pre-eclampsia at delivery discharge and assess external validation or model transportability across clinical sites. DESIGN: Prediction model using data available in the electronic health record from two clinical sites. SETTING: Two tertiary care health systems from the Southern (2014-2015) and Northeastern USA (2017-2019). POPULATION: A total of 28 201 postpartum individuals: 10 100 in the South and 18 101 in the Northeast. METHODS: An internal-external cross validation (IECV) approach was used to assess external validation or model transportability across the two sites. In IECV, data from each health system were first used to develop and internally validate a prediction model; each model was then externally validated using the other health system. Models were fit using penalised logistic regression, and accuracy was estimated using discrimination (concordance index), calibration curves and decision curves. Internal validation was performed using bootstrapping with bias-corrected performance measures. Decision curve analysis was used to display potential cut points where the model provided net benefit for clinical decision-making. MAIN OUTCOME MEASURES: The outcome was postpartum readmission for either hypertension or pre-eclampsia <6 weeks after delivery. RESULTS: The postpartum readmission rate for hypertension and pre-eclampsia overall was 0.9% (0.3% and 1.2% by site, respectively). The final model included six variables: age, parity, maximum postpartum diastolic blood pressure, birthweight, pre-eclampsia before discharge and delivery mode (and interaction between pre-eclampsia × delivery mode). Discrimination was adequate at both health systems on internal validation (c-statistic South: 0.88; 95% confidence interval [CI] 0.87-0.89; Northeast: 0.74; 95% CI 0.74-0.74). In IECV, discrimination was inconsistent across sites, with improved discrimination for the Northeastern model on the Southern cohort (c-statistic 0.61 and 0.86, respectively), but calibration was not adequate. Next, model updating was performed using the combined dataset to develop a new model. This final model had adequate discrimination (c-statistic: 0.80, 95% CI 0.80-0.80), moderate calibration (intercept -0.153, slope 0.960, Emax 0.042) and provided superior net benefit at clinical decision-making thresholds between 1% and 7% for interventions preventing readmission. An online calculator is provided here. CONCLUSIONS: Postpartum readmission for hypertension and pre-eclampsia may be accurately predicted but further model validation is needed. Model updating using data from multiple sites will be needed before use across clinical settings.

Metformin Plus Insulin for Preexisting Diabetes or Gestational Diabetes in Early Pregnancy: The MOMPOD Randomized Clinical Trial.

Importance: Insulin is recommended for pregnant persons with preexisting type 2 diabetes or diabetes diagnosed early in pregnancy. The addition of metformin to insulin may improve neonatal outcomes. Objective: To estimate the effect of metformin added to insulin for preexisting type 2 or diabetes diagnosed early in pregnancy on a composite adverse neonatal outcome. Design, Setting, and Participants: This randomized clinical trial in 17 US centers enrolled pregnant adults aged 18 to 45 years with preexisting type 2 diabetes or diabetes diagnosed prior to 23 weeks' gestation between April 2019 and November 2021. Each participant was treated with insulin and was assigned to add either metformin or placebo. Follow-up was completed in May 2022. Intervention: Metformin 1000 mg or placebo orally twice per day from enrollment (11 weeks -<23 weeks) through delivery. Main Outcome and Measures: The primary outcome was a composite of neonatal complications including perinatal death, preterm birth, large or small for gestational age, and hyperbilirubinemia requiring phototherapy. Prespecified secondary outcomes included maternal hypoglycemia and neonatal fat mass at birth, and prespecified subgroup analyses by maternal body mass index less than 30 vs 30 or greater and those with preexisting vs diabetes early in pregnancy. Results: Of the 831 participants randomized, 794 took at least 1 dose of the study agent and were included in the primary analysis (397 in the placebo group and 397 in the metformin group). Participants' mean (SD) age was 32.9 (5.6) years; 234 (29%) were Black, and 412 (52%) were Hispanic. The composite adverse neonatal outcome occurred in 280 (71%) of the metformin group and in 292 (74%) of the placebo group (adjusted odds ratio, 0.86 [95% CI 0.63-1.19]). The most commonly occurring events in the primary outcome in both groups were preterm birth, neonatal hypoglycemia, and delivery of a large-for-gestational-age infant. The study was halted at 75% accrual for futility in detecting a significant difference in the primary outcome. Prespecified secondary outcomes and subgroup analyses were similar between groups. Of individual components of the composite adverse neonatal outcome, metformin-exposed neonates had lower odds to be large for gestational age (adjusted odds ratio, 0.63 [95% CI, 0.46-0.86]) when compared with the placebo group. Conclusions and Relevance: Using metformin plus insulin to treat preexisting type 2 or gestational diabetes diagnosed early in pregnancy did not reduce a composite neonatal adverse outcome. The effect of reduction in odds of a large-for-gestational-age infant observed after adding metformin to insulin warrants further investigation. Trial Registration: ClinicalTrials.gov Identifier: NCT02932475.

Labor Induction versus Expectant Management in Low-Risk Nulliparous Women.

BACKGROUND: The perinatal and maternal consequences of induction of labor at 39 weeks among low-risk nulliparous women are uncertain. METHODS: In this multicenter trial, we randomly assigned low-risk nulliparous women who were at 38 weeks 0 days to 38 weeks 6 days of gestation to labor induction at 39 weeks 0 days to 39 weeks 4 days or to expectant management. The primary outcome was a composite of perinatal death or severe neonatal complications; the principal secondary outcome was cesarean delivery. RESULTS: A total of 3062 women were assigned to labor induction, and 3044 were assigned to expectant management. The primary outcome occurred in 4.3% of neonates in the induction group and in 5.4% in the expectant-management group (relative risk, 0.80; 95% confidence interval [CI], 0.64 to 1.00). The frequency of cesarean delivery was significantly lower in the induction group than in the expectant-management group (18.6% vs. 22.2%; relative risk, 0.84; 95% CI, 0.76 to 0.93). CONCLUSIONS: Induction of labor at 39 weeks in low-risk nulliparous women did not result in a significantly lower frequency of a composite adverse perinatal outcome, but it did result in a significantly lower frequency of cesarean delivery. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ARRIVE ClinicalTrials.gov number, NCT01990612 .).

Trends in Opioid and Psychotropic Prescription in Pregnancy in the United States From 2001 to 2015 in a Privately Insured Population : A Cross-sectional Study.

BACKGROUND: Opioid and psychotropic prescriptions are common during pregnancy. Little is known about coprescriptions of both medications in this setting. OBJECTIVE: To describe opioid prescription among women who are prescribed psychotropics compared with women who are not. DESIGN: Cross-sectional study. SETTING: U.S. commercial insurance beneficiaries from MarketScan (2001 to 2015). PARTICIPANTS: Pregnant women at 22 weeks' gestation or greater who were insured continuously for 3 months or more before pregnancy through delivery. MEASUREMENTS: Opioid prescription, dosage thresholds (morphine milligram equivalents [MME] of ≥50/day and ≥90/day), number of opioid agents (≥2), and duration (≥30 days) among those with and without prescription of psychotropics, from 2011 to 2015. RESULTS: Among 958 980 pregnant women, 10% received opioids only, 6% psychotropics only, and 2% opioids with coprescription of psychotropics. Opioid prescription was higher among women prescribed psychotropics versus those who were not (26.5% vs. 10.7%). From 2001 to 2015, psychotropic prescription overall increased from 4.4% to 7.6%, opioid prescription without coprescription of psychotropics decreased from 11.9% to 8.4%, and opioids with coprescription decreased from 28.1% to 22.0%. Morphine milligram equivalents of 50 or greater per day decreased for women with and without coprescription (29.6% to 17.3% and 22.8% to 18.5%, respectively); MME of 90 or greater per day also decreased in both groups (15.0% to 4.7% and 11.5% to 4.2%, respectively). Women prescribed opioids only were more likely to have an antepartum hospitalization compared with those with neither prescription, as were women with coprescription versus those prescribed psychotropics only. Compared with those prescribed opioids only, women with coprescriptions were more likely to exceed MME of 90 or greater per day and to be prescribed 2 or more opioid agents and for 30 days or longer. Number and duration of opioids increased with benzodiazepine and gabapentin coprescription. LIMITATION: Inability to determine appropriateness of prescribing or overdose events. CONCLUSION: Opioids are frequently coprescribed with psychotropic medication during pregnancy and are associated with antepartum hospitalization. A substantial proportion of pregnant women are prescribed opioids at doses that increase overdose risk and exceed daily recommendations. PRIMARY FUNDING SOURCE: None.

Missed Opportunities for Early Diabetes Screening in Pregnancy.

OBJECTIVE: This study aimed to identify characteristics of women at risk of undiagnosed type 2 diabetes mellitus (T2DM) that fail to receive early pregnancy screening. STUDY DESIGN: This was a retrospective case-control study of at-risk women who initiated care at the University of North Carolina at Chapel Hill at <21 weeks from January 2015 to December 2015. In 2013, the American College of Obstetricians and Gynecologists and the American Diabetes Association recommended women with prior GDM, glucose intolerance, or body mass index (BMI) ≥ 30 kg/m2 receive early pregnancy screening for undiagnosed T2DM. We defined early screening as 1-hour 50-g glucose challenge test or hemoglobin A1c at <21 weeks' gestation. Cases were women who did not have early screening, and controls were women who did. Modified Poisson regression with robust error variance estimated relative risks of factors associated with missed early screening. RESULTS: Of the 1,932 women who initiated care at <21 weeks, 257 (13%) women were at risk of undiagnosed T2DM and, thus, candidates for early screening. However, 129 (50.2%) women were not screened. Higher BMI and prior GDM were associated with a lower relative risk of missed screening. CONCLUSION: Higher BMI and prior GDM increased the likelihood of early diabetes screening, but only half of at-risk women were screened. Provider education and best practice alert systems are needed to increase screening for undiagnosed T2DM.

Placental growth factor predicts time to delivery in women with signs or symptoms of early preterm preeclampsia: a prospective multicenter study.

BACKGROUND: There is a robust association between altered angiogenic factor concentrations, which includes placental growth factor and clinically recognized preeclampsia. Alterations in concentrations of angiogenic factors precede the clinical onset of preeclampsia by several weeks. The temporal relationship between the measured angiogenic factors and the time to delivery in women with suspected preeclampsia at <35 weeks gestation, however, remains to be clarified. OBJECTIVE: The purposes of this study were to examine the relationship between placental growth factor and time to delivery in women at <35 weeks gestation with signs or symptoms of preeclampsia and to compare the performance of placental growth factor to other clinical markers for prediction of time to delivery in preeclampsia. STUDY DESIGN: Women with signs or symptoms of preeclampsia between 20.0 and 35.0 weeks gestation were enrolled in a prospective, observational study at 24 centers. Blood was collected at presentation for placental growth factor, and subjects were evaluated and treated according to local protocols. Clinical outcomes were obtained, and all final diagnoses were adjudicated by an independent expert panel according to 2013 American College of Obstetricians and Gynecologists' Hypertension in Pregnancy criteria. Placental growth factor was measured retrospectively on the Alere, Inc, triage platform. A normal placental growth factor was defined as >100 pg/mL; the assay's limit of detection is 12 pg/mL. Two-by-2 tables were constructed for comparison of test outcomes that included negative predictive value; time-to-delivery was analyzed by survival curves and Cox regression. RESULTS: Seven hundred fifty-three subjects were enrolled; 538 (71%) had a final diagnosis of preeclampsia; 542 (72%) delivered at <37 weeks gestation, and 358 (47%) delivered at <34 weeks gestation. Among the 279 women (37%) with a normal placental growth factor at presentation, the negative predictive value for preeclampsia delivered within 14 days or within 7 days was 90% and 93%, respectively. Compared with women with normal placental growth factor, women with placental growth factor ≤100 pg/mL have a hazard ratio of 7.17 (confidence interval, 5.08-10.13) in Cox regression for time to delivery after adjustment for both gestational age at enrollment and the final diagnosis of preeclampsia. The placental growth factor levels of normal (>100 pg/mL), low (12-100 pg/mL), and very low (<12 pg/mL) have well-separated distributions of time to delivery, with median values of 45, 10, and 2 days, respectively. Subjects with placental growth factor ≤100 pg/mL have a perinatal death rate of 5.7% and a small-for-gestational-age rate of 51.7%; subjects with placental growth factor >100 pg/mL have a perinatal death rate of 0% (no observations in this cohort) and an a small-for-gestational-age rate of 16.8%. CONCLUSION: In women with suspected preeclampsia at <35.0 weeks gestation, a low placental growth factor was correlated strongly with preterm delivery independent of a diagnosis of preeclampsia or gestational age at presentation, whereas a normal placental growth factor was associated with pregnancy prolongation, even in patients who ultimately had a final diagnosis of preeclampsia. This suggests that placental growth factor levels are superior to clinical markers in the prediction of adverse pregnancy in women with suspected preeclampsia.

Association Between Features of Spontaneous Late Preterm Labor and Late Preterm Birth.

OBJECTIVE: This study aimed to evaluate the association between clinical and examination features at admission and late preterm birth. STUDY DESIGN: The present study is a secondary analysis of a randomized trial of singleton pregnancies at 340/7 to 365/7 weeks' gestation. We included women in spontaneous preterm labor with intact membranes and compared them by gestational age at delivery (preterm vs. term). We calculated a statistical cut-point optimizing the sensitivity and specificity of initial cervical dilation and effacement at predicting preterm birth and used multivariable regression to identify factors associated with late preterm delivery. RESULTS: A total of 431 out of 732 (59%) women delivered preterm. Cervical dilation ≥ 4 cm was 60% sensitive and 68% specific for late preterm birth. Cervical effacement ≥ 75% was 59% sensitive and 65% specific for late preterm birth. Earlier gestational age at randomization, nulliparity, and fetal malpresentation were associated with late preterm birth. The final regression model including clinical and examination features significantly improved late preterm birth prediction (81% sensitivity, 48% specificity, area under the curve = 0.72, 95% confidence interval [CI]: 0.68-0.75, and p-value < 0.01). CONCLUSION: Four in 10 women in late-preterm labor subsequently delivered at term. Combination of examination and clinical features (including parity and gestational age) improved late-preterm birth prediction.

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.

Practice Variation in Antenatal Steroid Administration for Anticipated Late Preterm Birth: A Physician Survey.

OBJECTIVE: The objective of this study was to measure knowledge and practice variation in late preterm steroid use. STUDY DESIGN: Electronic survey of American College of Obstetricians and Gynecologists (ACOG) members about data supporting the ACOG/Society for Maternal-Fetal Medicine (SMFM) recommendations and practice when caring for women with anticipated late preterm birth (PTB), 340/7 to 366/7 weeks. RESULTS: Of 352 administered surveys, we obtained 193 completed responses (55%); 82.5% were generalist obstetrician-gynecologists (OB/GYNs), and 42% cared for women with anticipated late PTB at least weekly. Most believed that late preterm steroids provided benefit by reducing respiratory distress syndrome (93%), transient tachypnea of the newborn (83%), and neonatal intensive care unit admission (82%). More than half administered late preterm steroids to women with multiple gestations (73%), and pregestational diabetes (55-80%) depending on glycemic control. OB/GYNs administered steroids to insulin-dependent and poorly controlled diabetics more often than MFMs (75 vs. 46% and 59 vs. 37% respectively, p < 0.05 for both). While providers believed there was increased maternal hyperglycemia (88%) and neonatal hypoglycemia (59%), 88% believed neonatal respiratory benefits outweighed these risks. Respondents agreed research is needed to determine who are appropriate candidates (77%) and how to minimize adverse outcomes (82%). CONCLUSION: Most providers are administering late preterm steroids to all women, even those populations who have been excluded from previous trials. Despite widespread use, providers believe more research is needed to optimize management.

The Effect of Blood Loss on Cefazolin Levels in Women Undergoing Cesarean Delivery.

OBJECTIVE: To quantify the effects of operative blood loss during cesarean on tissue and plasma cefazolin concentrations. STUDY DESIGN: This was a prospective observational study of singleton pregnancies undergoing scheduled cesarean between 34 and 40 weeks. Cefazolin administered prior to skin incision. Maternal plasma samples were obtained (Time 1[T1]: immediately, T2: 20 minutes, T3: 40 minutes, and T4: 60 minutes after cefazolin infusion). Subcutaneous adipose tissue sampled before and after fascia. Primary outcome was subcutaneous adipose cefazolin level after fascial closure. Formal quantitative blood loss (QBL) performed. Women with higher QBL, those at/above 75% of QBL in this population, were compared with those with lower QBL (QBL below 75%). Data analyzed using bivariable statistics. RESULTS: Ninety-two women were screened, 32 were eligible, and 20 enrolled. Median QBL was 630 mL (interquartile range [IQR]: 473-818) and 1,160 mL (IQR: 1,000-1,560) in the low and high QBL groups, respectively. Demographics and operative characteristics were similar. Median adipose cefazolin level after fascial closure did not differ between the groups (3.5 vs. 3.9 µg/g, p = 0.75). No differences in maternal plasma cefazolin concentrations between the groups at any time point or in pharmacokinetic parameters were seen. CONCLUSION: Intraoperative maternal plasma concentrations and adipose levels of cefazolin are similar between women with high and low blood loss at the time of cesarean delivery.

Impact of Azithromycin-Based Extended-Spectrum Antibiotic Prophylaxis on Noninfectious Cesarean Wound Complications.

OBJECTIVE: Adding azithromycin to standard antibiotic prophylaxis for unscheduled cesarean delivery has been shown to reduce postcesarean infections. Because wound infection with ureaplasmas may not be overtly purulent, we assessed the hypothesis that azithromycin-based extended-spectrum antibiotic prophylaxis also reduces wound complications that are identified as noninfectious. STUDY DESIGN: This is a secondary analysis of the C/SOAP (Cesarean Section Optimal Antibiotic Prophylaxis) randomized controlled trial, which enrolled women with singleton pregnancies ≥24 weeks who were undergoing nonelective cesarean. Women were randomized to adjunctive azithromycin or identical placebo up to 1 hour preincision. All wound complications occurring within 6 weeks were adjudicated into infection and noninfectious wound complications (seroma, hematoma, local cellulitis, and other noninfectious wound breakdown). The primary outcome for this analysis is the composite of noninfectious wound complications. RESULTS: At a total of 14 sites, 2,013 women were randomized to adjunctive azithromycin (n = 1,019) or placebo (n = 994). Groups were similar at baseline. Although there was a lower rate of noninfectious wound complications in the azithromycin group compared with placebo (2.9 vs. 3.8%), this was not statistically significant (p = 0.22). CONCLUSION: While adding azithromycin to usual antibiotic prophylaxis for nonelective cesarean delivery does reduce the risk of postcesarean infections, it did not significantly reduce the risk of postcesarean noninfectious wound complications.

Maternal Gut Microbiome Biodiversity in Pregnancy.

OBJECTIVE: To measure maternal gut microbiome biodiversity in pregnancy. MATERIALS AND METHODS: In phase 1, maternal fecal samples were collected by rectal swab in 20 healthy pregnant women (14-28 weeks gestation) to measure bacterial abundance. In phase 2, fecal samples were collected from 31 women at enrollment (<20 weeks gestation, baseline) and at 36 to 39 weeks of gestation (follow-up). We assessed cluster analysis to assess bacterial community profiles at the phylum level longitudinally through pregnancy. DNA was extracted from swabs, followed by PCR of the bacterial 16s rRNA gene and multiplex high-throughput sequencing (Ion Torrent). RESULTS: In phase 1, 16 of 20 samples yielded usable data. White women (n = 10) had greater abundance of Firmicutes (23 ± 0.15 vs. 16% ± 0.75, p = 0.007) and Bacteroidetes (24 ± 0.14 vs. 19% ± 0.68, p = 0.015) compared with non-White women (n = 6). In the 11 paired specimens, Bacteroidetes increased in abundance from baseline to follow-up. Compared with women who gained weight below the median gestational weight gain (GWG, <15.4 kg), those who gained above the median GWG had increased abundance of Bacteroidetes (p = 0.02) and other phyla (p = 0.04). CONCLUSION: Maternal microbiome biodiversity changes as pregnancy progresses and correlates with GWG.

Risk-Reducing Salpingectomy Versus Standard Tubal Sterilization: Lessons From Offering Women Options for Interval Sterilization.

OBJECTIVES: In women receiving sterilization, the removal of the entire fallopian tube, a procedure referred to as a risk-reducing salpingectomy (RRS), reduces subsequent ovarian cancer risk compared with standard tubal sterilization procedures. There are limited data on which surgical procedure women will choose when educated about the benefits of an RRS. Our objective was to study the proportion of women desiring sterilization that would choose an RRS. METHODS: This cohort study included women 30 years of age and older with a living biological child who requested laparoscopic sterilization at a tertiary academic hospital. Participants were given a decision aid and offered an RRS or a standard tubal sterilization procedure with titanium clips. The primary outcome was to determine the proportion of women who would choose an RRS. Other outcomes included estimated blood loss and operative time, which was compared between groups, along with complications. RESULTS: Fourteen of the 18 (78%) women who participated in our study chose RRS. Estimated blood loss and operating time were similar among women who underwent RRS and standard tubal sterilizations. There were no significant complications in either group. The study was ended early based on emerging data and a change in national practice patterns. CONCLUSIONS: Because of the elective nature of sterilization and the complexities of cancer risk reduction, a patient-centered approach is beneficial for sterilization counseling. Our results support offering RRS as an alternative to standard tubal sterilization.

Prenatal exome sequencing in anomalous fetuses: new opportunities and challenges.

PurposeWe investigated the diagnostic and clinical performance of exome sequencing in fetuses with sonographic abnormalities with normal karyotype and microarray and, in some cases, normal gene-specific sequencing.MethodsExome sequencing was performed on DNA from 15 anomalous fetuses and from the peripheral blood of their parents. Parents provided consent to be informed of diagnostic results in the fetus, medically actionable findings in the parents, and their identification as carrier couples for significant autosomal recessive conditions. We assessed the perceptions and understanding of exome sequencing using mixed methods in 15 mother-father dyads.ResultsIn seven (47%) of 15 fetuses, exome sequencing provided a diagnosis or possible diagnosis with identification of variants in the following genes: COL1A1, MUSK, KCTD1, RTTN, TMEM67, PIEZO1 and DYNC2H1. One additional case revealed a de novo nonsense mutation in a novel candidate gene (MAP4K4). The perceived likelihood that exome sequencing would explain the results (5.2 on a 10-point scale) was higher than the approximately 30% diagnostic yield discussed in pretest counseling.ConclusionExome sequencing had diagnostic utility in a highly select population of fetuses where a genetic diagnosis was highly suspected. Challenges related to genetics literacy and variant interpretation must be addressed by highly tailored pre- and posttest genetic counseling.

Maternal obesity and major intraoperative complications during cesarean delivery.

BACKGROUND: Multiple studies have demonstrated an association between maternal obesity and postoperative complications, but there is a dearth of information about the impact of obesity on intraoperative complications. OBJECTIVE: To estimate the association between maternal obesity at delivery and major intraoperative complications during cesarean delivery (CD). METHODS: This is a secondary analysis of the deidentified Maternal-Fetal Medicine Unit Cesarean Registry of women with singleton pregnancies. Maternal body mass index (BMI) at delivery was categorized as BMI 18.5 to 29.9 kg/m2, BMI 30 to 39.9 kg/m2, BMI 40 to 49.9 kg/m2, and BMI ≥ 50 kg/m2. The primary outcome, any intraoperative complication, was defined as having at least 1 major intraoperative complication, including perioperative blood transfusion, intraoperative injury (bowel, bladder, ureteral injury; broad ligament hematoma), atony requiring surgical intervention, repeat laparotomy, and hysterectomy. Log-binomial models were used to estimate risk ratios of intraoperative complication in 2 models: model 1 adjusting for maternal race, and preterm delivery <37 weeks; and model 2 adjusting for confounders in Model 1 as well as emergency CD, and type of skin incision. RESULTS: A total of 51,218 women underwent CD; 38% had BMI 18.5 to 29.9 kg/m2, 47% BMI 30 to 39.9 kg/m2, 12% BMI 40 to 49.9 kg/m2 and 3% BMI ≥ 50 kg/m2. Having at least 1 intraoperative complication was uncommon (3.4%): 3.8% for BMI 18.5 to 29.9 kg/m2, 3.2% BMI 30 to 39.9 kg/m2, 2.6% BMI 40 to 49.9 kg/m2 and 4.3% BMI ≥ 50 kg/m2 (P < .001). In the fully adjusted model 2, women with BMI 40 to 49.9 kg/m2 had a lower risk of any intraoperative complication (adjusted risk ratio [ARR], 0.76; 95% confidence interval [CI], 0.64 to 0.89) compared with women with BMI 18.5 to 29.9 kg/m2. Women with BMI 30 to 39.9 kg/m2 (ARR, 0.93; 95% CI, 0.84 to 1.03) had a similar risk of any intraoperative complication compared with nonobese women. Among super obese women, there was evidence of effect modification by emergency CD. Compared with nonobese women, neither super obese women undergoing nonemergency CD (ARR, 1.13; 95% CI, 0.84 to 1.52) nor those undergoing emergency CD (ARR, 0.59; 95% CI, 0.32 to 1.10) had an increased risk of intraoperative complication. CONCLUSION: In contrast to the risk for postcesarean complications, the risk of intraoperative complication does not appear to be increased in obese women, even among those with super obesity.

Maternal super obesity and risk for intensive care unit admission in the MFMU Cesarean Registry.

INTRODUCTION: Obesity is a risk factor for intensive care unit (ICU) admission in nonpregnant populations. Less is known about maternal obesity and ICU admission risk. The objective of this study was to estimate the association between maternal obesity and ICU admission among women who delivered via cesarean section or vaginal birth after cesarean section (VBAC). MATERIAL AND METHODS: This is a retrospective cohort analysis of women who delivered via VBAC or cesarean section in the Maternal-Fetal Medicine Unit (MFMU) Cesarean Registry. We defined exposure as body mass index (BMI) at delivery stratified as non-obese (BMI 18.5-29.9 kg/m2 ), class I or II obese (BMI 30-39.9 kg/m2 ), morbidly obese (BMI 40-49.9 kg/m2 ), and super obese (BMI ≥ 50 kg/m2 ). The primary outcome was ICU admission. Modified Poisson regression models estimated relative risk (RR) of ICU admission by obesity strata, after adjusting for confounders. Mediation analysis was used to estimate the proportion of ICU admission risk attributable specifically to obesity. RESULTS: We included 68 455 women; 40% non-obese, 46% class I or II obese, 12% morbidly obese, and 2% super obese. Super obese women were at higher risk for ICU admission compared with non-obese women (0.7 vs. 1.3%, adjusted RR 1.61; 95% CI 1.01-2.65), after adjusting for confounders. Among super obese women, medical comorbidities mediated 58% of ICU admission risk, suggesting that a significant proportion of ICU admission is driven by maternal obesity. CONCLUSIONS: Super obese women who deliver by cesarean section or VBAC are at increased risk of peripartum ICU admission. Obstetricians and critical care specialists should consider possible ICU admission during delivery planning.

Identification of Epigenetic Factor Proteins Expressed in Human Embryonic Stem Cell-Derived Trophoblasts and in Human Placental Trophoblasts.

Human embryonic stem cells (hESCs) have been used to derive trophoblasts through differentiation in vitro. Intriguingly, mouse ESCs are prevented from differentiation to trophoblasts by certain epigenetic factor proteins such as Dnmt1, thus necessitating the study of epigenetic factor proteins during hESC differentiation to trophoblasts. We used stable isotope labeling by amino acids in cell culture and quantitative proteomics to study changes in the nuclear proteome during hESC differentiation to trophoblasts and identified changes in the expression of 30 epigenetic factor proteins. Importantly, the DNA methyltransferases DNMT1, DNMT3A, and DNMT3B were downregulated. Additionally, we hypothesized that nuclear proteomics of hESC-derived trophoblasts may be used for screening epigenetic factor proteins expressed by primary trophoblasts in human placental tissue. Accordingly, we conducted immunohistochemistry analysis of six epigenetic factor proteins identified from hESC-derived trophoblasts-DNMT1, DNMT3B, BAF155, BAF60A, BAF57, and ING5-in 6-9 week human placentas. Indeed, expression of these proteins was largely, though not fully, consistent with that observed in 6-9 week placental trophoblasts. Our results support the use of hESC-derived trophoblasts as a model for placental trophoblasts, which will enable further investigation of epigenetic factors involved in human trophoblast development.

Development and validation of a spontaneous preterm delivery predictor in asymptomatic women.

BACKGROUND: Preterm delivery remains the leading cause of perinatal mortality. Risk factors and biomarkers have traditionally failed to identify the majority of preterm deliveries. OBJECTIVE: To develop and validate a mass spectrometry-based serum test to predict spontaneous preterm delivery in asymptomatic pregnant women. STUDY DESIGN: A total of 5501 pregnant women were enrolled between 17(0/7) and 28(6/7) weeks gestational age in the prospective Proteomic Assessment of Preterm Risk study at 11 sites in the United States between 2011 and 2013. Maternal blood was collected at enrollment and outcomes collected following delivery. Maternal serum was processed by a proteomic workflow, and proteins were quantified by multiple reaction monitoring mass spectrometry. The discovery and verification process identified 2 serum proteins, insulin-like growth factor-binding protein 4 (IBP4) and sex hormone-binding globulin (SHBG), as predictors of spontaneous preterm delivery. We evaluated a predictor using the log ratio of the measures of IBP4 and SHBG (IBP4/SHBG) in a clinical validation study to classify spontaneous preterm delivery cases (<37(0/7) weeks gestational age) in a nested case-control cohort different from subjects used in discovery and verification. Strict blinding and independent statistical analyses were employed. RESULTS: The predictor had an area under the receiver operating characteristic curve value of 0.75 and sensitivity and specificity of 0.75 and 0.74, respectively. The IBP4/SHBG predictor at this sensitivity and specificity had an odds ratio of 5.04 for spontaneous preterm delivery. Accuracy of the IBP4/SHBG predictor increased using earlier case-vs-control gestational age cutoffs (eg, <35(0/7) vs ≥35(0/7) weeks gestational age). Importantly, higher-risk subjects defined by the IBP4/SHBG predictor score generally gave birth earlier than lower-risk subjects. CONCLUSION: A serum-based molecular predictor identifies asymptomatic pregnant women at risk of spontaneous preterm delivery, which may provide utility in identifying women at risk at an early stage of pregnancy to allow for clinical intervention. This early detection would guide enhanced levels of care and accelerate development of clinical strategies to prevent preterm delivery.

Maternal Super Obesity and Neonatal Morbidity after Term Cesarean Delivery.

Objective To estimate the association between maternal super obesity (body mass index [BMI] ≥ 50 kg/m(2)) and neonatal morbidity among neonates born via cesarean delivery (CD). Methods Retrospective cohort of singleton neonates delivered via CD ≥ 37 weeks in the Maternal-Fetal Medicine Unit Cesarean Registry. Maternal BMI at delivery was stratified as 18.5 to 29.9 kg/m(2), 30 to 39.9 kg/m(2), 40 to 49.9 kg/m(2), and ≥ 50 kg/m(2). Primary outcomes included acute (5-minute Apgar score < 5, cardiopulmonary resuscitation and ventilator support < 24 hours, neonatal injury, and/or transient tachypnea of the newborn) and severe (grade 3 or 4 intraventricular hemorrhage, necrotizing enterocolitis, seizure, respiratory distress syndrome, hypoxic ischemic encephalopathy, meconium aspiration, ventilator support ≥ 2 days, sepsis and/or neonatal death) neonatal morbidity. Odds of neonatal morbidity were estimated for each BMI category adjusting for clinical and operative characteristics. Results Of 41,262 maternal-neonatal dyads, 36% of women were nonobese, 49% had BMI of 30 to 39.9 kg/m(2), 12% had BMI of 40 to 49.9 kg/m(2), and 3% were super obese. Compared with nonobese women, super obese women had twofold odds of acute (5 vs. 10%; adjusted odds ratio [aOR]: 1.81, 95% confidence interval [CI]: 1.59-2.73) and severe (3 vs. 6%; aOR: 2.08; 95% CI: 1.59-2.73) neonatal morbidity. Conclusion Among term infants delivered via CD, maternal super obesity is associated with increased risk of neonatal morbidity.