Mark Allen Clapp

OBJECTIVE: To determine whether and to what extent hospitals across the United States vary in their use of late preterm steroids. METHODS: This was a retrospective cohort study of singleton births with known gestational ages identified in the Premier Healthcare Database from 2015 to 2022. The primary variable of interest was hospital-level adoption of antenatal corticosteroid use for late preterm singleton deliveries, calculated as the proportion of late preterm singleton births (34–36 completed weeks of gestation) with any betamethasone exposure during the same late preterm period. Hospital adoption was defined as the weighted average rate of steroid administration among late preterm births across the entire postperiod. Hospitals were ranked by their late preterm steroid adoption rates and categorized by quartile based on the empirical distribution. Temporal trends were assessed using annual hospital-level adoption rates and visualized using time series plots and distributional plots. A logistic regression model was constructed to identify hospital characteristics associated with being a highest-quartile adopter. RESULTS: The analysis cohort included 726 hospitals and 5,109,270 births, of which 309,837 (6.1%) were singleton late preterm births. Hospital steroid exposure rates ranged from 0% to 92% and were categorized into quartiles based on overall exposure rate, with cutoffs at 22.4%, 33.9%, and 45.1%. Median exposure rates increased progressively across quartiles, from 15.4% (IQR 10.0–18.9%) in the lowest-adopting hospitals (quartile 1) to 54.3% (IQR 49.1–61.0%) in the highest-adopting hospitals (quartile 4), with substantial within-quartile variation. In the multivariable model, urban location was a strong predictor of high adoption after adjustment (adjusted odds ratio [aOR] 2.03; 95% CI, 1.04–4.02, P =.04). Compared with Midwestern hospitals, Southern hospitals had significantly lower odds of being high adopters (aOR 0.32; 95% CI, 0.17–0.61, P <.001). Among clinical case mix variables, a higher proportion of late preterm births at 34 weeks of gestation was strongly associated with high adoption (aOR 2.39; 95% CI, 1.73–3.36, P <.001). CONCLUSION: After the publication of the ALPS (Antenatal Late Preterm Steroids) trial, the adoption of late preterm steroid use was heterogeneous among U.S. hospitals. These findings highlight the need for a more in-depth exploration of local factors that drive the adoption of evidence-based practices outside of observable hospital characteristics.

Given the challenges in accurately predicting birth timing, we sought to quantify the proportion of individuals who receive late-preterm steroids in routine clinical practice who ultimately deliver at term. This retrospective cohort study of singleton gestations used data from January 2021 to December 2024 from the Premier Healthcare Database. We calculated the proportion of late-preterm steroid exposures in women who delivered at term and analyzed rates by hospital. The cohort included 519 hospitals and 97,322 singleton delivery hospitalizations of women with late-preterm betamethasone exposure. Of these, 28.8% (28,021) delivered at term, which equated to 1.0% (28,021 of 2,800,799) of all singleton term births being exposed to late-preterm steroids. Adjusted hospital-level proportions of singleton term births in individuals exposed to late-preterm steroids ranged from 0% to 63% with a median of 29%, reflecting substantial heterogeneity in late-preterm steroid use. This study highlights the need to develop accurate prediction methods for preterm birth timing and policies to inform optimal late-preterm steroid use.

Objective: To determine whether and to what extent hospitals across the United States vary in their use of late-preterm steroids using a novel data set in which the timing of steroid administration relative to delivery can be observed. Methods: This was a retrospective cohort study of singleton births with known gestational ages identified in the Premier Healthcare Database from 2015 to 2022. The primary variable of interest was hospital-level adoption of antenatal corticosteroids for late-preterm singleton deliveries, calculated as the proportion of late-preterm singleton births (34-36 completed weeks of gestation) with any betamethasone exposure during the same late-preterm period. Hospital adoption was defined as the weighted average rate of ALPS administration among late-preterm infants across the entire post-period. Hospitals were ranked by their late-preterm steroid adoption rates and categorized by quartile based on the empirical distribution. Temporal trends were assessed using annual hospital-level adoption rates and visualized using time-series plots and distributional plots. A logistic regression model was constructed to determine hospital characteristics associated with being a highest-quartile adopting hospital. Results: The analysis cohort included 728 hospitals and 5,452,791 births, of which 361,006 (6.6%) were singleton late preterm births. Hospital steroid exposure rates ranged from 0 to 82% and were categorized into quartiles based on overall exposure rate, with cutoffs at 20.6%, 29.8%, and 40.1%. Median exposure rates increased progressively across quartiles from 14.1% (IQR 9.3-17.4%) in the lowest adopting hospitals (Q1) to 47.6% (IQR 43.7-53.2%) in the highest adopting hospitals (Q4), with substantial within-quartile variation. In the multivariable model, urban location was a strong predictor of high adoption after adjustment (aOR 2.05; 95% CI 1.11-3.83, p=0.02). Compared to Midwest hospitals, Southern hospitals had significantly lower odds of being high adopters (aOR 0.37; 95% CI 0.20-0.69, p<0.01). Among clinical case mix variables, a higher proportion of late preterm births at 34 weeks’ gestation was strongly associated with high adoption (aOR 2.21; 95% CI 1.58-3.14, p<0.001). Conclusion: Following publication of the ALPS Trial, there was heterogeneous adoption of late preterm steroids among US hospitals. These findings highlight the need for a more in-depth exploration of local factors that drive the adoption of evidence-based practices outside of observable hospital characteristics.

Importance: Cesarean delivery is the most common surgery in the US with more than 1 million performed each year; it is also the most significant risk factor for postpartum infection. The Cesarean Section Optimal Antibiotic Prophylaxis trial demonstrated that the addition of azithromycin at the time of cesarean birth performed in labor reduces postpartum infection. Objective: To determine the real-world adoption and effect of this trial on clinical practice and postpartum infections among U.S. pregnant persons undergoing cesarean delivery in labor. Design: Difference-in-differences analysis from 2013-2024. Setting: Population-based, patient-level analysis using Epic Cosmos, a large longitudinal national electronic health record database of patients seen in health systems using Epic. Participants: Pregnant individuals who received outpatient prenatal care in the system, who labored and gave birth to a liveborn singleton infant at 24-43 weeks of gestation were included. Exclusion criteria included unknown mode of delivery and intraamniotic infection. Exposures: The treatment group included those delivered by cesarean and the control group included those who delivered vaginally. The pre-period was defined as 2013-2016, excluding a washout period from trial publication until December 31, 2016, and the post-period was defined from 2017-2024. Main Outcomes and Measures: The primary outcomes were perioperative azithromycin administration and postpartum infection within 6 weeks of delivery. Results: 1,663,341 participants were included in the final analysis. In the pre- and post-periods, azithromycin was administered in 0.01% and 0.04% of vaginal births and in 2.2% and 39.6% of cesarean births, respectively. In the pre- and post-periods, postpartum infection occurred in 2.0% and 2.7% of vaginal births and 9.2% and 8.0% of cesarean births. In the adjusted difference-in-difference analysis, the trial resulted in an absolute increase in azithromycin use by 37.6 percentage points (pp) (95% CI: 33.1 to 42.2 pp); postpartum infection decreased by 2.0 pp (95% CI: -2.5 to -1.4 pp), a relative decrease of 20%. Conclusions and Relevance: Outside the clinical trial setting, this study provides evidence that azithromycin significantly reduces postpartum infection among pregnant persons undergoing a cesarean delivery in labor. Key Points: Question: Did evidence from the Cesarean Section Optimal Antibiotic Prophylaxis (C/SOAP) trial change real-world clinical practice and decrease postpartum infections among U.S. pregnant persons who underwent a cesarean delivery in labor? Findings: In this difference-in-differences analysis of 1.6 million births, azithromycin use increased 37.6 percentage points and postpartum infections decreased by 2.0 percentage points following the C/SOAP trial. Meaning: Outside the clinical trial setting, this study provides evidence that azithromycin significantly reduces postpartum infection among individuals having a cesarean delivery in labor.

INTRODUCTION: In 2021, the Society for Maternal-Fetal Medicine updated its guidance on late preterm antenatal steroids, which included a recommendation to engage in shared decision-making on the risks and benefits. The objective of this study was to assess the effects of this updated guidance on the practice among a contemporary cohort of US births. METHODS: This retrospective cohort study implemented an interrupted time series (ITS) design among late preterm singleton births using encounter-level inpatient data from the Premier Healthcare Database (PHD). A 3-year observational period before (January 1, 2019, to December 31, 2021) and after (January 1, 2022, to December 31, 2024) the intervention date (selected as January 1, 2022) was defined to quantify whether the guideline was associated with changes in obstetric practice. Steroid exposure was modeled at the patient level as a binary outcome using Poisson regression with a log-link function, with a linear spline at the intervention knot to estimate both the pre-intervention slope and the change in slope following guideline dissemination. The change in slope at the knot was the primary parameter of interest. Time was measured in quarters. Incidence rate ratios can be interpreted as quarter percent changes (QPCs) in the rate of ACS use and are presented with 95% confidence intervals (CIs). RESULTS: 342,925 late preterm deliveries were included in the analysis: 176,938 in the pre-period and 165,987 in the post-period. 57,372 (32.4%) in the pre-period were exposed to late preterm steroids, and exposure rates were stable over time (adjusted QPC (aQPC) 1.01; 95% CI: 1.00, 1.01). Following guideline dissemination, steroid exposure rates declined by 3% per quarter (aQPC 0.97; 95% CI: 0.96, 0.98), indicating a significant change in the trajectory of steroid use among the population targeted by the guideline. In quarter 4 of 2024 (the end of the study period), the exposure rate decreased to 25.1%. CONCLUSION: Late preterm steroid exposure decreased significantly after SMFM updated its clinical guidance, which newly highlighted the conflicting long-term data and recommended shared decision-making about the risks and benefits. Future research on the long-term risks and benefits of ACS is needed to inform clinical practice guidelines and shared decision-making. Key Points: Following SMFM’s 2021 updated guidance on late preterm antenatal corticosteroids, which highlighted uncertain long-term neurodevelopmental risks and recommended individualized counseling, steroid exposure among late preterm births declined by approximately 3% per quarter in a nationally representative US cohort.

Importance: Patients are often monitored closely during pregnancy, then face barriers to transitioning to primary care after delivery. These barriers may contribute to a reliance on acute care for primary care–treatable concerns. Objectives: To evaluate the association of an intervention that increased postpartum primary care engagement over the first year after delivery with overall acute care (emergency department [ED] and urgent care center [UC]) use and acute care use for primary care–treatable concerns (ie, nonemergency conditions or conditions typically managed by a primary care practitioner [PCP]). Design, Setting, and Participants: This is a nonprespecified secondary analysis of a randomized clinical trial (RCT) conducted from November 3, 2022, to October 11, 2023, at 1 hospital-based clinic and 5 community-based obstetric clinics at a large academic medical center. The 353 participants included English- and Spanish-speaking pregnant or recently postpartum adults with 1 or more comorbidities and an assigned PCP. Exposure: This behavioral science–informed intervention included default scheduling of postpartum PCP appointments within 4 months post partum and tailored messages and reminders about the appointments and the importance of postpartum primary care. Main Outcome and Measures: Main outcomes included the use of any acute care and the number of acute care visits during the postpartum period, as well as the use of acute care and the number of visits specifically for primary care–treatable concerns (based on the reason for visit). Ordinary least-squares regression, adjusted for randomization strata and patient demographic and health characteristics, was used to assess the association of the intervention with the use of acute care. Outcomes were analyzed using an intent-to-treat approach. Results: A total of 353 patients (mean [SD] age, 34.1 [4.9] years) were enrolled in the RCT (control, 173 [49.0%]; intervention, 180 [51.0%]). The intervention had no statistically significant association with overall postpartum acute care use, but it was associated with decreased acute care use for primary care–treatable concerns (control, 70 of 173 [40.5%]; intervention, 53 of 180 [29.4%]); in the adjusted model, the intervention was associated with in a 10.2–percentage point reduction in these visits (95% CI, −20.4 to −0.04 percentage points). The intervention was also associated with a reduced number of visits for primary care–treatable concerns (control: mean [SD], 0.7 [1.1] visits; intervention: mean [SD], 0.4 [0.8] visits), corresponding to a reduction of 0.3 visits (95% CI, −0.5 to −0.1 visits) in the adjusted model. Conclusions and Relevance: In this secondary analysis of an RCT, a behavioral science–informed intervention that increased postpartum primary care engagement was associated with decreased acute care use for primary care–treatable concerns. The results suggest that supporting postpartum transitions to primary care may reduce reliance on acute care, perhaps by facilitating greater care coordination and early detection and management of chronic conditions in the primary care setting. Trial Registration: ClinicalTrials.gov Identifier: NCT05543265

OBJECTIVE: To provide real-world data to inform benchmarking goals and practical issues that influence optimal antenatal corticosteroid timing and to examine patient factors, such as gestational age at steroid administration and presenting diagnoses, associated with steroid administration in relation to delivery. METHODS: This is a retrospective cohort study of singleton deliveries between July 1, 2016, and December 31, 2024, at two large academic hospitals with level IV neonatal intensive care units in a single health system. The primary cohort of interest was individuals who delivered between 24 0/7 and 33 6/7 weeks of gestation. The primary outcome of interest was the timing of antenatal corticosteroid administration in relation to delivery, categorized as none, delivery between 6 hours and 7 days after the first dose of antenatal corticosteroid (“optimally timed” per the Society for Maternal-Fetal Medicine’s quality metric), and delivery less than 6 hours or more than 7 days after the first dose of antenatal corticosteroid (“suboptimally timed”). As a balancing measure to optimally timed antenatal corticosteroid administration, we also examined those who received antenatal corticosteroids before 34 weeks of gestation and delivered at term (after 37 weeks). We reported the rates of optimal timing and term delivery by their corresponding weeks of gestation and performed multivariable logistic regression modeling to understand patient factors and diagnoses associated with antenatal corticosteroid timing. RESULTS: Among the 1,694 pregnant patients who delivered before 34 weeks of gestation, 961 (56.7%) had optimally timed antenatal corticosteroid administration, 162 (9.6%) received the first dose of antenatal corticosteroids less than 6 hours before delivery, 320 (18.9%) delivered more than 7 days after antenatal corticosteroid administration, and 251 (14.8%) did not receive antenatal corticosteroids. Of those who received antenatal steroids before 34 weeks of gestation, 747 of 2,879 (25.9%) delivered at term. There was little variation in optimal timing or term delivery by gestational age. Clinical factors associated with optimally timed antenatal corticosteroid administration compared with delivery more than 7 days after administration included pregnancy-related hypertensive disorder (adjusted odds ratio [aOR] 1.88, 95% CI, 1.31–2.69), preterm labor (aOR 2.78, 95% CI, 1.32–5.81), premature rupture of membranes (1.37, 95% CI, 1.33–1.42), anxiety disorder (aOR 079, 95% CI, 0.76–0.83), multiparous with no history of preterm birth (aOR 0.81, 95% CI, 0.77–0.86), placenta previa (aOR 0.76, 95% CI, 0.68–0.84), and placenta accreta (aOR 0.83, 95% CI, 0.81–0.85). CONCLUSION: Achieving optimal timing of antenatal corticosteroid administration remains challenging. These findings underscore the need for improved prediction of preterm delivery and individualized patient assessment to ensure timely access to antenatal corticosteroids for women at risk of preterm birth while reducing unnecessary exposure.

The ARRIVE trial showed that induction of labor in low-risk nulliparous individuals at 39 weeks reduced cesarean delivery. We sought to determine whether publication of the ARRIVE trial was associated with changes in the rate of induction of labor at 40 weeks, and if so, whether similar changes were seen in the rate of cesarean delivery. This was a repeated cross-sectional analysis using US natality data from February 2017 to August 2019. Low-risk nulliparous individuals delivering a non-anomalous, cephalic, singleton infant were included; exclusion criteria included hypertension, diabetes, or small-for-gestational age infant. The primary outcome was induction of labor at 40 weeks. Secondary outcomes included cesarean delivery and a composite of adverse neonatal outcomes. A population-level interrupted time series analysis was performed. The pre-period ran from February 2017 to January 2018, the dissemination period from February to August 2018, and the post-period from September 2018 to August 2019. The study included 843,133 individuals (339,978 in the pre-period; 190,479 in the dissemination or washout period; 312,676 in the post-period). The rate of induction of labor at 40 weeks increased from a predicted rate of 18.7% to an observed rate of 20.2% (IRR, 1.08, 95% CI: 1.05–1.12) in the post-period. The rate of cesarean delivery and adverse neonatal outcomes in the cohort did not change at the start of the post-period (cesarean delivery: 25.3% predicted vs. 25.2% observed, IRR, 1.00, 95% CI: 0.96–1.03; adverse neonatal outcome: 5.3% predicted vs. 5.0% observed, IRR, 0.95, 95% CI: 0.87–1.02). Dissemination of the ARRIVE trial was associated with an increase in the rate of induction at 40 weeks among patients who remained pregnant after 39 weeks. However, there was no population-level decrease in cesarean delivery, suggesting that the benefits of induction of labor may not extrapolate to this cohort.

OBJECTIVE: To assess whether a postpartum hemorrhage (PPH) risk stratification tool using structured data in the electronic health record (EHR) could be developed and validated with information known before the third trimester. METHODS: We performed a retrospective cohort study of individuals receiving prenatal care and delivering at a single academic institution between January 1, 2017, and December 31, 2023. The cohort included individuals who established care before 24 weeks of gestation, delivered at or after 24 weeks, and had a recorded estimated blood loss at the time of delivery. The cohort was subdivided into three groups for model development: 1) training (66.0% of deliveries between 2017 and 2022), 2) testing (33.0% of deliveries between 2017 and 2022), and 3) temporal validation (deliveries in 2023). We performed traditional and machine-learning modeling approaches in the training data. Discrimination and calibration were compared by calculating the area under the receiver operating characteristic curve and constructing calibration curves; a single approach was selected to identify a predicted probability to classify patients as high risk of PPH, which we defined as two or more times the increased risk of PPH and without exceeding a screen-positive rate of 20% (or twice the estimated baseline rate of PPH in the population). RESULTS: A total of 17,201 patients were included and split between the three cohorts: 10,060 in the training set, 5,183 in the testing set, and 1,958 in the temporal validation set. Model discrimination and calibration were similar among all approaches. Model parsimony was used to select the final modeling approach: logistic regression with stepwise backward selection. This approach yielded an area under the curve of 0.689 (95% CI, 0.667–0.715) and 0.659 (95% CI, 0.621–0.694) in the testing and validation data. Among those classified as high risk, the screen-positive rates and positive predictive values were 19.2% (95% CI, 18.1–20.3%) and 20.1% (95% CI, 17.8–22.7%) in the testing set and 21.6% (95% CI, 19.9–23.4%) and 21.3% (95% CI, 17.7–25.5%) in the validation sets. CONCLUSION: Using structured EHR data known by 24 weeks of gestation, we developed a prenatal risk stratification model for PPH. This model was designed to be used for predelivery planning and health optimization, particularly among those at the highest risk of PPH and its subsequent morbidity, in contrast to other tools that stratify risk after admission of for delivery.