Placental Histopathologic Findings of a Large Cohort of Patients With SARS-CoV-2 Infection During Pregnancy.

Pregnant individuals with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are at a higher risk for adverse pregnancy outcomes. Previous small cohort studies have shown increased frequency of placental lesions associated with maternal vascular malperfusion, fetal vascular malperfusion, and inflammation among patients with SARS-CoV-2, without controlling for cardiometabolic risk factors among many such patients. We aimed to evaluate whether SARS-CoV-2 infection during pregnancy is independently associated with placental abnormalities when controlling for risk factors that could affect placental histopathology. Retrospective cohort study of placentas from singleton pregnancies in Kaiser Permanente Northern California from March to December 2020. Pathologic findings were compared among those with confirmed cases of SARS-CoV-2 during pregnancy and those without. We examined the association between SARS-CoV-2 infection and categorical placental pathologies, controlling for maternal age, gestational age, prepregnancy body mass index, gestational hypertension, preeclampsia/eclampsia, preexisting diabetes, history of thrombosis, and stillbirth. A total of 2,989 singleton gestation placentas were analyzed, 416 (13%) from pregnancies with SARS-CoV-2 infection and 2,573 (86%) from those without infection. Among placentas from pregnancies with SARS-CoV-2, 54.8% had evidence of inflammation, 27.1% maternal malperfusion abnormality, 20.7% massive perivillous fibrin or chronic villitis, 17.3% villous capillary abnormality, and 15.1% fetal malperfusion. After controlling for risks factors and stratifying interval time between SARS-CoV-2 infection and delivery, no association was found between placental abnormalities and SARS-CoV-2 infection during pregnancy. SARS-CoV-2 infection was not associated with an increased risk of placentally mediated adverse outcomes during pregnancy, compared with placentas sent for other indications, in this large diverse cohort.

Development and validation of prediction models for gestational diabetes treatment modality using supervised machine learning: a population-based cohort study.

BACKGROUND: Gestational diabetes (GDM) is prevalent and benefits from timely and effective treatment, given the short window to impact glycemic control. Clinicians face major barriers to choosing effectively among treatment modalities [medical nutrition therapy (MNT) with or without pharmacologic treatment (antidiabetic oral agents and/or insulin)]. We investigated whether clinical data at varied stages of pregnancy can predict GDM treatment modality. METHODS: Among a population-based cohort of 30,474 pregnancies with GDM delivered at Kaiser Permanente Northern California in 2007-2017, we selected those in 2007-2016 as the discovery set and 2017 as the temporal/future validation set. Potential predictors were extracted from electronic health records at different timepoints (levels 1-4): (1) 1-year preconception to the last menstrual period, (2) the last menstrual period to GDM diagnosis, (3) at GDM diagnosis, and (4) 1 week after GDM diagnosis. We compared transparent and ensemble machine learning prediction methods, including least absolute shrinkage and selection operator (LASSO) regression and super learner, containing classification and regression tree, LASSO regression, random forest, and extreme gradient boosting algorithms, to predict risks for pharmacologic treatment beyond MNT. RESULTS: The super learner using levels 1-4 predictors had higher predictability [tenfold cross-validated C-statistic in discovery/validation set: 0.934 (95% CI: 0.931-0.936)/0.815 (0.800-0.829)], compared to levels 1, 1-2, and 1-3 (discovery/validation set C-statistic: 0.683-0.869/0.634-0.754). A simpler, more interpretable model, including timing of GDM diagnosis, diagnostic fasting glucose value, and the status and frequency of glycemic control at fasting during one-week post diagnosis, was developed using tenfold cross-validated logistic regression based on super learner-selected predictors. This model compared to the super learner had only a modest reduction in predictability [discovery/validation set C-statistic: 0.825 (0.820-0.830)/0.798 (95% CI: 0.783-0.813)]. CONCLUSIONS: Clinical data demonstrated reasonably high predictability for GDM treatment modality at the time of GDM diagnosis and high predictability at 1-week post GDM diagnosis. These population-based, clinically oriented models may support algorithm-based risk-stratification for treatment modality, inform timely treatment, and catalyze more effective management of GDM.

Society for Maternal-Fetal Medicine Consult Series #62: Best practices in equitable care delivery-Addressing systemic racism and other social determinants of health as causes of obstetrical disparities.

The Centers for Disease Control and Prevention define social determinants of health as "the conditions in the places where people live, learn, work, and play" that can affect health outcomes. Systemic racism is a root cause of the power and wealth imbalances that affect social determinants of health, creating disproportionate rates of comorbidities and adverse outcomes in the communities of racial and ethnic minority groups. Focusing primarily on disparities between Black and White individuals born in the United States, this document reviews the effects of social determinants of health and systemic racism on reproductive health outcomes and recommends multilevel approaches to mitigate disparities in obstetrical outcomes.

Association Between Neighborhood Deprivation in Early Pregnancy and Gestational Diabetes Mellitus.

OBJECTIVE: To evaluate whether having a pregnancy in a deprived neighborhood was associated with an increased risk of gestational diabetes mellitus (GDM) compared with having a pregnancy in the least-deprived neighborhoods. METHODS: This was a retrospective observational cohort study of pregnant individuals within Kaiser Permanente Northern California from 2011 to 2018 with residential history from prepregnancy through 24 weeks of gestation and clinical data from prepregnancy through delivery. The primary outcome was a diagnosis of GDM. Neighborhood deprivation was characterized with an index aggregating multiple indicators of Census tract-level sociodemographic information. Mediation analysis using inverse odds ratio weighting estimated the mediation effects of prepregnancy body mass index (BMI), gestational weight gain, smoking tobacco, and illegal drug use before GDM diagnosis. RESULTS: Overall, 214,375 pregnant individuals were included, and 11.3% had a diagnosis of GDM. Gestational diabetes prevalence increased with neighborhood deprivation from 10.0% in the lowest Neighborhood Deprivation Index quintile to 12.7% in the highest quintile. Compared with pregnant individuals in the least deprived neighborhoods (quintile 1), pregnant individuals in quintiles 2-5 had elevated risk of GDM (relative risk [95% CI]) when adjusted for maternal age, parity, insurance type, and residential history (quintile 2, 1.17 [1.10-1.23]; quintile 3, 1.38 [1.30-1.46]; quintile 4, 1.54 [1.45-1.63]; quintile 5, 1.71 [1.62-1.82]). There was a dose-response relationship between relative risk of GDM and increasing quintile of neighborhood deprivation (P for trend <.001). Prepregnancy BMI mediated 45.8% (95% CI, 40.9-50.7%) of the association. Other potential mediators were found to mediate a small if not negligible proportion of this association (2.4-3.6%). CONCLUSION: Neighborhood deprivation was associated with GDM, and a considerable proportion of this relationship was mediated by prepregnancy BMI.

Perinatal Outcomes After Bariatric Surgery Compared With a Matched Control Group.

OBJECTIVE: To evaluate perinatal outcomes associated with pregnancy after bariatric surgery within a large integrated health care system using propensity score matching. METHODS: We conducted a retrospective cohort study that evaluated perinatal outcomes in pregnant patients after bariatric surgery from January 2012 through December 2018. History of bariatric surgery was identified by using International Classification of Diseases codes and a clinical database. Primary outcomes were preterm birth (PTB), gestational hypertension, preeclampsia, impaired glucose tolerance or gestational diabetes, a large-for-gestational-age (LGA) or small-for-gestational-age (SGA) neonates, and cesarean birth. Propensity scores were estimated by using logistic regression that accounted for age at delivery, prepregnancy body mass index, year of delivery, parity, neighborhood deprivation index, race and ethnicity, insurance status, initiation of prenatal visit in the first trimester, smoking during pregnancy, chronic hypertension, and preexisting diabetes. Five patients in the control group were matched to each patient in the case group on linear propensity score, and modified Poisson regression was used to adjust for covariates. Sensitivity analyses by timing and type of surgery were performed. RESULTS: We identified a case cohort of 1,591 pregnancies in patients after bariatric surgery and a matched cohort of 7,955 pregnancies in patients who had not undergone bariatric surgery. Demographic characteristics were similar in both groups. In multivariate models, pregnancy after bariatric surgery was associated with a decreased risk of preeclampsia (7.5% vs 10.2%, adjusted relative risk [aRR] 0.72, 95% CI 0.60-0.86), gestational diabetes or impaired fasting glucose (23.5% vs 35.0%, aRR 0.73, 95% CI 0.66-0.80), and LGA (10.6% vs 19.9%, aRR 0.56, 95% CI 0.48-0.65) and an increased risk of SGA (10.9% vs 6.6%, aRR 1.51, 95% CI 1.28-1.78). No significant differences were observed in PTB, gestational hypertension and cesarean delivery. CONCLUSION: Pregnancy after bariatric surgery in a racially and ethnically diverse cohort of patients is associated with decreased risk of preeclampsia, gestational diabetes or impaired fasting glucose, and LGA neonates; it is also associated with an increased risk of SGA neonates compared with pregnant patients in a matched control group.

A first look at chorioamnionitis management practice variation among US obstetricians.

Objective. To examine practice patterns for diagnosis and treatment of chorioamnionitis among US obstetricians. Study Design. We distributed a mail-based survey to members of the American College of Obstetricians and Gynecologists, querying demographics, practice setting, and chorioamnionitis management strategies. We performed univariable and multivariable analyses. Results. Of 500 surveys distributed, 53.8% were returned, and 212 met study criteria and were analyzed. Most respondents work in group practice (66.0%), perform >100 deliveries per year (60.0%), have been in practice >10 years (77.3%), and work in a nonuniversity setting (85.1%). Temperature plus one additional criterion (61.3%) was the most common diagnostic strategy. Over 25 different primary antibiotic regimens were reported, including use of a single agent by 30.0% of respondents. A wide range of postpartum antibiotic duration was reported from no postpartum treatment (34.5% after vaginal delivery, 11.3% after cesarean delivery) to 48 hours of postpartum treatment (24.7% after vaginal delivery, 32.1% after cesarean delivery). No practitioner characteristic was independently associated with diagnostic or therapeutic strategies in multivariable analysis. Conclusion. There is a wide variation in contemporary clinical practices for the management of chorioamnionitis. This may represent a dearth of level I evidence. Future prospective clinical trials may provide more evidence-based practice recommendations for diagnosis and treatment of chorioamnionitis.

Glycemic Control Trajectories and Risk of Perinatal Complications Among Individuals With Gestational Diabetes.

Importance: Glycemic control is the cornerstone of gestational diabetes management. Glycemic control trajectories account for differences in longitudinal patterns throughout pregnancy; however, studies on glycemic control trajectories are scarce. Objective: To examine whether glycemic control trajectories from gestational diabetes diagnosis to delivery were associated with differential risk of perinatal complications. Design, Setting, and Participants: This population-based cohort study included individuals with gestational diabetes with longitudinal electronic health record data from preconception to delivery who received prenatal care at Kaiser Permanente Northern California (KPNC) and were enrolled in KPNC's telemedicine-based gestational diabetes care program between January 2007 and December 2017. Data analysis was conducted from September 2021 to January 2022. Exposures: Glycemic control trajectories were derived using latent class modeling based on the American Diabetes Association's recommended self-monitoring of blood glucose measurements. Optimal glycemic control was defined as at least 80% of all measurements meeting the targets at KPNC clinical settings. Main Outcomes and Measures: Multivariable Poisson regression models were used to estimate the associations of glycemic control trajectories with cesarean delivery, preterm birth, shoulder dystocia, large- and small-for-gestational-age, and neonatal intensive care unit admission and stay of 7 days or longer. Results: Among a total of 26 774 individuals (mean [SD] age, 32.9 [5.0] years; 11 196 Asian or Pacific Islander individuals [41.8%], 1083 Black individuals [4.0%], 7500 Hispanic individuals [28.0%], and 6049 White individuals [22.6%]), 4 glycemic control trajectories were identified: stably optimal (10 528 individuals [39.3%]), rapidly improving to optimal (9151 individuals [34.2%]), slowly improving to near-optimal (4161 individuals [15.5%]), and slowly improving to suboptimal (2934 individuals [11.0%]). In multivariable models with the rapidly improving to optimal trajectory group as the reference group, glycemic control trajectories were associated with perinatal complications with a gradient across stably optimal to slowly improving to suboptimal. For individuals in the stably optimal trajectory group, there were lower risks of cesarean delivery (adjusted relative risk [aRR], 0.93 [95% CI, 0.89-0.96]), shoulder dystocia (aRR, 0.75 [95% CI, 0.61-0.92]), large-for-gestational age (aRR, 0.74 [95% CI, 0.69-0.80]), and neonatal intensive care unit admission (aRR, 0.90 [95% CI, 0.83-0.97]), while for patients in the slowly improving to suboptimal glycemic control trajectory group, risks were higher for cesarean delivery (aRR, 1.18 [95% CI, 1.12-1.24]; (P for trend < .001), shoulder dystocia (aRR, 1.41 [95% CI, 1.12-1.78]; P for trend < .001), large-for-gestational-age (aRR, 1.42 [95% CI, 1.31-1.53]; P for trend < .001), and neonatal intensive care unit admission (aRR, 1.33 [95% CI, 1.20-1.47]; P for trend < .001). The risk of small-for-gestational-age was higher in patients in the stably optimal group (aRR, 1.10 [95% CI, 1.02-1.20]) and lower in the slowly improving to suboptimal group (aRR, 0.63 [95% CI, 0.53-0.75]). Conclusions and Relevance: These findings suggest that slowly improving to near-optimal and slowly improving to suboptimal glycemic control trajectories were associated with increased risk of perinatal complications. Future interventions should help individuals achieve glycemic control early after gestational diabetes diagnosis and throughout pregnancy to decrease the risk of perinatal complications.

Do adhesions at repeat cesarean delay delivery of the newborn?

OBJECTIVE: We sought to assess whether the presence and severity of adhesions at first repeat cesarean delivery are associated with delayed delivery of the newborn. STUDY DESIGN: We conducted secondary analysis of a prospective cohort of women undergoing first repeat cesarean. Severity and location of adhesions were reported by surgeons immediately postoperatively. We compared adhesion density scores with delivery data. RESULTS: Of 145 women analyzed, 92 (63.5%) had adhesions and 53 (36.5%) did not. Mean incision to delivery time in women with adhesion scores >3 was 19.8 minutes, compared to 15.6 minutes with scores ≤ 3 (P = .04). More women with adhesion scores >3 remained undelivered at 30 minutes after incision compared to scores ≤ 3 (17.9% vs 5.1%; odds ratio, 7.6; 95% confidence interval, 1.6-34.5), after controlling for potential confounders. CONCLUSION: Among women undergoing first repeat cesarean, severity of adhesions may delay delivery of the newborn. Study of techniques to reduce adhesions may be warranted to prevent delayed delivery at repeat cesarean.

Neonatal medical admission in a term and late-preterm cohort exposed to magnesium sulfate.

OBJECTIVE: The purpose of this study was to estimate neonatal intensive care unit and special care unit (NICU) admission rates and care needs among term and late-preterm neonates who are exposed to antenatal magnesium sulfate. STUDY DESIGN: We conducted a retrospective cohort study of all singleton neonates of ≥35 weeks' gestation who were exposed immediately antenatally to magnesium sulfate for maternal eclampsia prophylaxis (August 2006 through July 2008). RESULTS: Fifty-one of 242 neonates (21.1%) who, at ≥35 weeks' gestation, had been exposed to antenatal magnesium sulfate were admitted to the NICU. NICU admission was associated in a dose-dependent fashion with total hours and mean dose of magnesium: >12 hours exposure, odds ratio, 2.81 (95% confidence interval, 1.31-6.03); >30 g exposure, odds ratio, 2.59 (95% confidence interval, 1.22-5.51). Infants in NICU who were diagnosed with hypermagnesemia required fluid or nutritional support more frequently (91.3% vs 39.3%; P < .001) than those without hypermagnesemia. CONCLUSION: Antenatal magnesium sulfate exposure is associated with NICU admission among term and late-preterm neonates in a dose-dependent fashion. Fluid and nutritional assistance commonly are needed in this cohort.

COVID-19 prevalence, symptoms, and sociodemographic disparities in infection among insured pregnant women in Northern California.

BACKGROUND: Research on COVID-19 during pregnancy has mainly focused on women hospitalized for COVID-19 or other reasons during their pregnancy. Little is known about COVID-19 in the general population of pregnant women. OBJECTIVE: To describe the prevalence of COVID-19, symptoms, consequent healthcare use, and possible sources of COVID-19 exposure among a population-based sample of pregnant women residing in Northern California. METHODS: We analyzed data from 19,458 members of Kaiser Permanente Northern California who were pregnant between January 2020 and April 2021 and responded to an online survey about COVID-19 testing, diagnosis, symptoms, and their experiences during the COVID-19 pandemic. Medical diagnosis of COVID-19 during pregnancy was defined separately by self-report and by documentation in electronic health records (EHR). We examined relationships of COVID-19 with sociodemographic factors, underlying comorbidities, and survey measures of COVID-19-like symptoms, consequent healthcare utilization, and possible COVID-19 exposures. RESULTS: Among 19,458 respondents, the crude prevalence of COVID-19 was 2.5% (n = 494) according to self-report and 1.4% (n = 276) according to EHR. After adjustment, the prevalence of self-reported COVID-19 was higher among women aged <25 years compared with women aged ≥35 years (prevalence ratio [PR], 1.75, 95% CI: 1.23, 2.49) and among Hispanic women compared with White women (PR, 1.91, 95% CI: 1.53, 2.37). Prevalence of self-reported COVID-19 was higher among women affected by personal or partner job loss during the pandemic (PR, 1.23, 95% CI: 1.02, 1.47) and among women living in areas of high vs. low neighborhood deprivation (PR, 1.74, 95% CI: 1.33, 2.27). We did not observe differences in self-reported COVID-19 between women with and without underlying comorbidities. Results were similar for EHR-documented COVID-19. Loss of smell or taste was a unique and common symptom reported among women with COVID-19 (42.3% in self-reported; 54.0% in EHR-documented). Among women with symptomatic COVID-19, approximately 2% were hospitalized, 71% had a telehealth visit, and 75% quarantined at home. Over a third of women with COVID-19 reported no known exposure to someone with COVID-19. CONCLUSIONS: Observed COVID-19 prevalence differences by sociodemographic and socioeconomic factors underscore social and health inequities among reproductive-aged women. Women with COVID-19 reported unique symptoms and low frequency of hospitalization. Many were not aware of an exposure to someone with COVID-19.

Racial, Ethnic, and Geographic Differences in Vaginal Birth After Cesarean Delivery in the US, 2011-2021.

This cross-sectional study examines racial, ethnic, and geographic differences in vaginal birth after cesarean delivery in the US, from 2011 to 2021.

Does length of labor vary by maternal age?

OBJECTIVE: The purpose of this study was to examine lengths of first and second stages of labor across maternal age groups to determine whether different norms should be established. STUDY DESIGN: We conducted a retrospective cohort study of all laboring, term, singleton, and cephalic deliveries at a single institution between 1980-2001. Median lengths of labor were compared among 6 maternal age groups. Statistical comparisons were made using Kruskal-Wallis and Wilcoxon rank sum tests. Multivariable linear and logistic regression models were performed. RESULTS: Among 31,976 births, length of labor differed significantly by maternal age for both nulliparous and multiparous women. Younger nulliparous women (age, <20 yrs) had a shorter median second stage by up to 97 minutes (P < .001) than older nulliparous women (age, >39 yrs). After we controlled for potential confounders, we found that older women had a persistently higher likelihood of experiencing longer labor and prolonged labor than younger women. CONCLUSION: Length of labor and prolonged labor increases with increasing maternal age.

Are there ethnic differences in the length of labor?

OBJECTIVE: The purpose of this study was to examine the lengths of the first and second stages of labor among different racial/ethnic groups to determine whether different norms should be established. STUDY DESIGN: This was a retrospective cohort study of all laboring, term, singleton, vertex deliveries in a single academic institution. Median lengths of first and second stages of labor were compared among 4 racial/ethnic groups: black, Asian, white, and Latina. Kruskal-Wallis, Wilcoxon rank sum tests, and multivariate linear and logistic regression models were performed. RESULTS: In 27,521 births, the lengths of first stage of labor did not differ significantly among groups in the multivariate analysis. In the second stage of labor, black women had shorter labors, both overall and stratified by epidural use. In the multivariate analysis, when controlled for demographics, parity, epidural, chorioamnionitis, birthweight, delivery year, and labor management, black women had a shorter second stage than did white women (nulliparous women, 22 minutes; multiparous women, 7.5 minutes; P < .001) and lower rates of prolonged second stage (odds ratio, 0.6; P < .001). Nulliparous Asian women had a significantly longer second stage and higher rates of prolonged second stage, and nulliparous Latina women had a shorter second stage, compared with nulliparous white women. CONCLUSION: When data are controlled for confounding factors, black women had a shorter length of second stage of labor than did women in other ethnic groups. These differences appear to be clinically significant. This contributes to the support of a multifactorial redefinition of labor curves, which are used widely in the management of labor.