Antenatal Late Preterm Steroids Research Articles

Antenatal Late Preterm Steroids: The Evolution of the ALPS Trial.

The Antenatal Late Preterm Steroids (ALPS) trial was designed to address respiratory morbidity common in infants born late preterm. The study was published in April, 2016 and, shortly thereafter, changed clinical practice in obstetrics in the United States. The following chapter describes the ALPS trial study design in detail, including the background leading to the trial, the study outcomes, and the initial findings of the long-term follow-up study. The ALPS story would not be complete without Elizabeth Thom, PhD, who died before her time. Her brilliance largely contributed to the design of the ALPS trial.

Neurodevelopmental Outcomes After Late Preterm Antenatal Corticosteroids

The Antenatal Late Preterm Steroids (ALPS) trial changed clinical practice in the United States by finding that antenatal betamethasone at 34 to 36 weeks decreased short-term neonatal respiratory morbidity. However, the trial also found increased risk of neonatal hypoglycemia after betamethasone. This follow-up study focused on long-term neurodevelopmental outcomes after late preterm steroids. To evaluate whether administration of late preterm (34-36 completed weeks) corticosteroids affected childhood neurodevelopmental outcomes. Prospective follow-up study of children aged 6 years or older whose birthing parent had enrolled in the multicenter randomized clinical trial, conducted at 13 centers that participated in the Maternal-Fetal Medicine Units (MFMU) Network cycle from 2011-2016. Follow-up was from 2017-2022. Twelve milligrams of intramuscular betamethasone administered twice 24 hours apart. The primary outcome of this follow-up study was a General Conceptual Ability score less than 85 (-1 SD) on the Differential Ability Scales, 2nd Edition (DAS-II). Secondary outcomes included the Gross Motor Function Classification System level and Social Responsiveness Scale and Child Behavior Checklist scores. Multivariable analyses adjusted for prespecified variables known to be associated with the primary outcome. Sensitivity analyses used inverse probability weighting and also modeled the outcome for those lost to follow-up. Of 2831 children, 1026 enrolled and 949 (479 betamethasone, 470 placebo) completed the DAS-II at a median age of 7 years (IQR, 6.6-7.6 years). Maternal, neonatal, and childhood characteristics were similar between groups except that neonatal hypoglycemia was more common in the betamethasone group. There were no differences in the primary outcome, a general conceptual ability score less than 85, which occurred in 82 (17.1%) of the betamethasone vs 87 (18.5%) of the placebo group (adjusted relative risk, 0.94; 95% CI, 0.73-1.22). No differences in secondary outcomes were observed. Sensitivity analyses using inverse probability weighting or assigning outcomes to children lost to follow-up also found no differences between groups. In this follow-up study of a randomized clinical trial, administration of antenatal corticosteroids to persons at risk of late preterm delivery, originally shown to improve short-term neonatal respiratory outcomes but with an increased rate of hypoglycemia, was not associated with adverse childhood neurodevelopmental outcomes at age 6 years or older.

Equivalence of single and standard doses of antenatal corticosteroids for late preterm neonatal outcomes: insights from a secondary analysis

BackgroundThe recent paradigm shift of treating individuals at risk of late preterm birth with antenatal corticosteroids warrants an assessment of the effect of single dosage. ObjectiveTo compare outcomes of neonates born in the late preterm period (34.0-36.6 weeks) following a single dose of antenatal corticosteroids versus placebo. Study designWe performed a secondary analysis of the Antenatal Late Preterm Steroids (ALPS) trial (Gyamfi-Bannerman C. et al.). All individuals enrolled in the parent trial who received only a single dose of either antenatal corticosteroids or placebo and delivered within 24 hours were included. Primary outcome was a composite of respiratory support at 72 hr., including continuous positive airway pressure or high flow nasal cannula ≥ 2 h, oxygen with an inspired fraction of ≥ 30% for ≥ 4 h, or mechanical ventilation. ResultsOf the 2,831 individuals in the parent trial, 1,083 (38.3%) met inclusion criteria; of them, 539 (49.8%) received a single dose of antenatal corticosteroids and 544 (50.2%) a single placebo dose. The placebo and antenatal corticosteroids groups had similar demographic and clinical characteristics. There was no difference in the rate of the primary respiratory outcome (aRR 1.12, 95% CI 0.85-1.47) or in the rate of respiratory distress syndrome (aRR 1.47, 95% CI 0.95-2.26) between those who received a single antenatal corticosteroids dose or placebo. An exploratory stratification by randomization-to-delivery intervals of 12-hour increments also showed no association with lower primary respiratory outcome rates. ConclusionIn individuals with late preterm birth pregnancies who received antenatal corticosteroids and delivered before a second dose, there were no differences in neonatal respiratory morbidities compared to placebo.

Gestational diabetes mellitus and late preterm birth: outcomes with and without antenatal corticosteroid exposure

BackgroundUnlike pregestational diabetes, ACOG recommends antenatal corticosteroids in those with GDM at risk for preterm birth. However, this recommendation is based on limited data, only 10.6% of the Antenatal Late Preterm Steroids (ALPS) study sample had GDM. There is a paucity of data on the risk of neonatal respiratory and other morbidity in this population. ObjectiveTo examine respiratory outcomes in parturients with GDM who received antenatal corticosteroids and delivered during the late preterm period versus those who did not. Material and MethodsThis population-based cohort study used the U.S. Vital Statistics dataset between 2016 to 2020. The inclusion criteria were singleton, non-anomalous individuals who delivered between 34.0 to 36.6 weeks with GDM and known status of antepartum corticosteroid exposure. The primary outcome, a composite neonatal adverse outcome (CNAO), included: Apgar score < 5 at 5 minutes, immediate assisted ventilation, assisted ventilation> 6 hours, surfactant use, seizure, or neonatal mortality. The secondary outcome was composite maternal adverse outcome (CMAO) including maternal blood transfusion, ruptured uterus, unplanned hysterectomy, and admission to the intensive care unit (ICU). Multivariable Poisson regression models were used to estimate adjusted relative risks (aRR) and 95% confidence intervals (CI). Average annual percent change (AAPC) was calculated to assess changes in rates of corticosteroid exposure over the study period. ResultsOf 19 million births during the study period, 110,197 (0.6%) met inclusion criteria, and among them, 23,028 (20.9%) individuals with GDM received antenatal corticosteroids. The rate of antenatal steroid exposure remained stable over the 5 years (APC=10.7, 95% CI: -5.4, 29.4). The CNAO was significantly higher among those who received corticosteroids than those who did not (137.1 versus 216.5 per 1,000 live births; aRR 1.24, 95% CI 1.20-1.28). Three components of the CNAO—immediate assisted ventilation, intubation > 6 hours, and surfactant use—were significantly higher with exposure than without. Additionally, the CMAO was significantly higher among those who received corticosteroids (aRR 1.34, 95% CI 1.18-1.52). Three components of CMAO—admission to ICU, blood transfusion, and unplanned hysterectomy—were significantly higher among the exposed group. Subgroup analysis, among large-for-gestational age, by gestational age, and race and ethnicity, confirm the trend of increased likelihood of adverse outcomes with exposure to corticosteroid. ConclusionIndividuals with GDM and antenatal corticosteroid exposure versus those unexposed, who delivered in the late preterm were at higher risk of neonatal and maternal adverse outcomes.

Regional Variation in Antenatal Late Preterm Steroid Use Following the ALPS Trial

The publication of the Antenatal Late Preterm Steroids (ALPS) trial in February 2016 demonstrated that antenatal administration of betamethasone in the late preterm period (between 34 to 36 weeks of gestation) for individuals with a high risk of delivery decreased neonatal respiratory morbidity. National estimates have suggested the trial did change obstetric practice, but little is known if the evidence was adopted uniformly or equitably. To assess regional variation in the use of late preterm steroids after the publication of the Antenatal Late Preterm Steroids (ALPS) Trial and to understand factors associated with a region's pace of adoption. This cross-sectional study used US natality data from February 2015 to October 2017 from hospital referral regions (HRRs) within the US. Inclusion criteria included live-born, nonanomalous, singleton, late preterm (34 to 36 completed weeks of gestation) neonates born to individuals without pregestational diabetes. This study was conducted from November 15, 2022, to January 13, 2023. HRRs were categorized as either a slower adopter or faster adopter of antenatal late preterm steroids based on the observed vs expected pace of antenatal steroid adoption in a 1-year period after the trial's dissemination. Patient and regional factors hypothesized a priori to be associated with the uptake of late preterm steroids were compared between faster and slower adopters. Comparisons were made using Student t test or Wilcoxon rank-sum test, as appropriate. A multivariable logistic regression was constructed to identify factors associated with faster adopter status in the postperiod. There were 666 097 late preterm births in 282 HRRs. The mean (SD) maternal age in HRRs was 27.9 (1.2) years. The median (IQR) percentage of births by race categories in HRRs for patients identifying as American Indian or Alaskan Native was 0.5% (0.2%-1.3%); Asian or Pacific Islander, 3.0% (1.7%-5.3%); Black, 12.9% (5.1%-29.1%); and White, 78.6% (66.6%-87.0%). The median percentage of births in HRRs to patients of Hispanic ethnicity was 11.2% (6.3%-27.4%). In this study, 136 HRRs (48.2%) were classified as faster adopters and 146 (51.8%) were classified as slower adopters. Faster adopters increased their steroid use by 12.1 percentage points (from 5.9% to 18.0%) compared with a 5.5 percentage point increase (from 3.7% to 9.2%) among slower adopters (P < .001). Most examined patient and regional factors were not associated with a region's pace of adoption, with the exception of the regional prevalence of prior preterm birth (adjusted odds ratio [aOR], 2.04 [95% CI, 1.48-2.82]) and the percentage of deliveries at 34 to 35 weeks of gestation (aOR, 0.68 [95% CI, 0.47-0.99]) compared with 36 weeks. In this cross-sectional study, there was widespread geographic variation in the adoption of antenatal steroid administration for late preterm births that largely remained unexplained by population factors. These findings should prompt further investigations to barriers to timely or equitable access to new evidence-based practices and guide future dissemination strategies with the goal of more uniform adoption.

648 Indications for antenatal late preterm steroids and childhood neurodevelopmental outcomes

648 Indications for antenatal late preterm steroids and childhood neurodevelopmental outcomes

Post Antenatal Late Preterm Steroids trial: interrupted time series analysis of respiratory outcomes in twin and pregestational diabetes

The Antenatal Late Preterm Steroids trial found that corticosteroid administration decreased respiratory complications by 20% among late preterm singleton deliveries. After the Antenatal Late Preterm Steroids trial, corticosteroid administration increased by 76% among twin pregnancies and 113% among singleton pregnancies complicated by pregestational diabetes mellitus compared with expected rates based on the pre-Antenatal Late Preterm Steroids trial trend. However, the effect of corticosteroids on twin pregnancies and pregnancies complicated by pregestational diabetes mellitus is not well studied, as the Antenatal Late Preterm Steroids trial excluded twin pregnancies and pregnancies complicated by pregestational diabetes mellitus. This study aimed to examine the change in the incidence rate of immediate assisted ventilation use and ventilation use for more than 6 hours among 2 populations after the dissemination of the Antenatal Late Preterm Steroids trial at the population level. This study was a retrospective analysis of publicly available US birth certificate data. The study period was from August 1, 2014, to April 30, 2018. The dissemination period of the Antenatal Late Preterm Steroids trial was from February 2016 to October 2016. Population-based interrupted time series analyses were performed for 2 target populations: (1) twin pregnancies not complicated by pregestational diabetes mellitus and (2) singleton pregnancies complicated by pregestational diabetes mellitus. For both target populations, analyses were limited to individuals who delivered nonanomalous live neonates between 34 0/7 and 36 6/7 weeks of gestation (vaginal or cesarean delivery). As a sensitivity analysis, a total of 23 placebo tests were conducted before (5 tests) and after (18 tests) the dissemination period. For the analysis of late preterm twin deliveries, 191,374 individuals without pregestational diabetes mellitus were identified. For the analysis of late preterm singleton pregnancy with pregestational diabetes mellitus, 21,395 individuals were identified. After the dissemination period, the incidence rate of immediate assisted ventilation use for late preterm twin deliveries was significantly lower than the expected value based on the pre-Antenatal Late Preterm Steroids trial trend (11.6% observed vs 13.0% expected; adjusted incidence rate ratio, 0.87; 95% confidence interval, 0.78-0.97). The incidence rate of ventilation use for more than 6 hours among late preterm twin deliveries did not change significantly after the dissemination of the Antenatal Late Preterm Steroids trial. A significant increase in the incidence rate of immediate assisted ventilation use and ventilation use for more than 6 hours was found among singleton pregnancies with pregestational diabetes mellitus. However, the results of placebo tests suggested that the increase in incidence was not necessarily due to the dissemination period of the Antenatal Late Preterm Steroids trial. The dissemination of the Antenatal Late Preterm Steroids trial was associated with decreased incidence of immediate assisted ventilation use, but no change in ventilation use for more than 6 hours, among late preterm twin deliveries in the United States. In contrast, the incidence of neonatal respiratory outcomes among singleton deliveries with pregestational diabetes mellitus did not decrease after the dissemination of the Antenatal Late Preterm Steroids trial.

Antenatal Corticosteroid Prophylaxis at Late Preterm Gestation: Clinical Guidelines Versus Clinical Practice

ObjectiveWe investigated how the Antenatal Late Preterm Steroids (ALPS) trial findings have been translated into clinical practice in Canada and the United States (U.S.). MethodsThe study included all live births in Nova Scotia, Canada, and the U.S. from 2007 to 2020. Antenatal corticosteroids (ACS) administration within specific categories of gestational age was assessed by calculating rates per 100 live births, and temporal changes were quantified using odds ratio (OR) and 95% confidence intervals (CI). Temporal trends in optimal and suboptimal ACS use were also assessed. ResultsIn Nova Scotia, the rate of any ACS administration increased significantly among women delivering at 350 to 366 weeks, from 15.2% in 2007–2016 to 19.6% in 2017–2020 (OR 1.36, 95% CI 1.14–1.62). Overall, the U.S. rates were lower than the rates in Nova Scotia. In the U.S., rates of any ACS administration increased significantly across all gestational age categories: among live births at 350 to 366 weeks gestation, any ACS use increased from 4.1% in 2007–2016 to 18.5% in 2017–2020 (OR 5.33, 95% CI 5.28–5.38). Among infants between 240 and 346 weeks gestation in Nova Scotia, 32% received optimally timed ACS, while 47% received ACS with suboptimal timing. Of the women who received ACS in 2020, 34% in Canada and 20% in the U.S. delivered at ≥37 weeks. ConclusionPublication of the ALPS trial resulted in increased ACS administration at late preterm gestation in Nova Scotia, Canada, and the U.S. However, a significant fraction of women receiving ACS prophylaxis delivered at term gestation.

Impact of antenatal late preterm steroids on neonatal respiratory outcomes in patients with pregestational diabetes

Impact of antenatal late preterm steroids on neonatal respiratory outcomes in patients with pregestational diabetes

Late preterm antenatal corticosteroids in singleton and twin gestations: a retrospective cohort study

BackgroundIn 2016, the American College of Obstetricians and Gynecologists recommended antenatal corticosteroids in the late preterm period for women at risk for preterm delivery. Limited real-world evidence exists on neonatal outcomes, particularly for twin gestations, following the guideline change. The study objective is to determine the association of antenatal corticosteroids in late preterm singleton and twin pregnancies with respiratory complications and hypoglycemia in a real-world clinical setting.MethodsThis is a retrospective cohort study comprising late preterm deliveries (4,341 mother–child pairs) within the Mount Sinai Health System, 2012–2018. The exposure of interest is antenatal corticosteroid administration of betamethasone during pregnancy between 34 0/7 and 36 6/7 weeks. Our primary outcomes are neonatal respiratory complications and hypoglycemia. Multivariable logistic regression was used to estimate the association between antenatal corticosteroid exposure and these two outcomes. We stratified the study population by singleton gestations and twins to minimize the potential confounding from different obstetric management between the two groups.ResultsAmong a total of 4,341 mother–child pairs (3,309 singleton and 1,032 twin mother–child pairs), 745 mothers received betamethasone, of which 40.94% (305/745) received the full course. Relative to no treatment, a full course of betamethasone was associated with reduced odds of respiratory complications (OR = 0.53, 95% CI:[0.31–0.85], p < 0.01) and increased odds of hypoglycemia (OR = 1.86, 95%CI:[1.34–2.56], p < 0.01) in singletons; however, the association with respiratory complications was not significant in twins (OR = 0.42, 95% CI:[0.11–1.23], p = 0.16), but was associated with increased odds of hypoglycemia (OR = 2.18, 95% CI:[1.12–4.10], p = 0.02).A partial course of betamethasone (relative to no treatment) was not significantly associated with any of the outcomes, other than respiratory complications in twins (OR = 0.34, 95% CI:[0.12–0.82], p = 0.02).ConclusionsExposure to antenatal corticosteroids in singletons and twins is associated with increased odds of hypoglycemia. Among singletons, exposure to the full dosage (i.e. two doses) was associated with decreased odds of respiratory complications but this was only the case for partial dose among twins. Twin gestations were not studied by the Antenatal Late Preterm Steroids trial. Therefore, our study findings will contribute to the paucity of evidence on the benefit of antenatal corticosteroids in this group. Health systems should systematically monitor guideline implementations to improve patient outcomes.

US Incidence of Late-Preterm Steroid Use and Associated Neonatal Respiratory Morbidity After Publication of the Antenatal Late Preterm Steroids Trial, 2015–2017

(Abstracted from JAMA Netw Open 2022;5:e2212702) In 2016, the antenatal late preterm steroids (ALPS) trial found that corticosteroids reduced the risk of respiratory complications in late-preterm neonates by 20%. The publication of this large-scale randomized clinical trial built upon previous findings that the antenatal administration of steroids decreased neonatal respiratory morbidity.

Neonatal outcomes by delivery indication after administration of antenatal late preterm corticosteroids

Antenatal corticosteroids, specifically betamethasone, administered to patients at risk for late preterm delivery have been associated with reduced rates of neonatal respiratory complications. However, whether these risks vary by delivery indication among betamethasone-exposed, late-preterm infants is not known. This study aimed to evaluate if spontaneous preterm labor or preterm prelabor rupture of membranes, compared with indicated late preterm delivery, is associated with better neonatal respiratory outcomes after accounting for betamethasone administration in the late preterm period. This was a secondary analysis of the Antenatal Late Preterm Steroids trial, a multicenter, placebo-controlled trial in which patients with singleton pregnancies at risk for delivery at 34 0/7 to 36 5/7 weeks of gestation were randomized to a single course of antenatal corticosteroids (betamethasone) or placebo. Patients were eligible if they had spontaneous preterm labor, preterm prelabor rupture of membranes, or if they were undergoing indicated late preterm delivery. The primary outcome was a composite of need for respiratory support, stillbirth, or neonatal death within 72 hours after delivery. Secondary outcomes included individual neonatal morbidities. Bivariate analyses were performed, and multivariable logistic regression models were used to control for potential confounders. Using the indicated preterm delivery group as the reference group, adjusted odds ratios and 95% confidence intervals were calculated for the outcomes by delivery indication. Subgroup analyses separately examined the treatment and placebo groups to determine the odds of the primary outcome by delivery indication. Of 2827 participants at high risk for late preterm delivery, 1427 (50.5%) received betamethasone. There were 790 (27.9%) infants born after preterm labor, 620 (21.9%) born after preterm prelabor rupture of membranes, and 1417 (50.1%) born after indicated preterm delivery. Compared with indicated preterm delivery, the odds of the primary outcome were lower among those born after preterm labor (7.3% vs 16.4%; adjusted odds ratio, 0.57; 95% confidence interval, 0.40-0.82) and among those born after preterm prelabor rupture of membranes (12.4% vs 16.4%; adjusted odds ratio, 0.49; 95% confidence interval, 0.35-0.69). Preterm labor had lower odds of all neonatal complications except feeding problems, and preterm prelabor rupture of membranes had lower odds of all neonatal complications except newborn intensive care unit admission for ≥3 days when compared with indicated preterm delivery. For the placebo group, the odds of the primary outcome were lower for the preterm labor group (8.2% vs 18.5%; adjusted odds ratio, 0.55; 95% confidence interval, 0.34-0.91) and the preterm prelabor rupture of membranes group (13.2% vs 18.5%; adjusted odds ratio, 0.46; 95% confidence interval, 0.29-0.73) than for the indicated preterm delivery group. For those exposed to betamethasone, the odds of the primary outcome remained lower for the preterm labor group (6.5% vs 14.3%; adjusted odds ratio, 0.58; 95% confidence interval, 0.34-0.99) and the preterm prelabor rupture of membranes group (11.7% vs 14.3%, adjusted odds ratio, 0.56; 95% confidence interval, 0.34-0.91) than for the indicated preterm delivery group. Compared with indicated preterm delivery, preterm labor and preterm prelabor rupture of membranes were associated with reduced odds of neonatal respiratory complications irrespective of betamethasone exposure in the late preterm period.

Indication Creep of Antenatal Late Preterm Steroids.

While antenatal corticosteroids (ACS) administered in the late preterm period have been shown to reduce respiratory morbidity, this finding was demonstrated in a well-designed randomized controlled trial (the Antenatal Betamethasone for Women at Risk for Late Preterm Delivery [ALPS]) with strict inclusion/exclusion criteria that may differ from clinical practice. The aim of this study was to investigate whether there has been indication creep since use of late preterm ACS became standard of care. Retrospective cohort study of pregnant women who received late preterm ACS between 2016 and 2019 were identified and separated into epochs of 2016 to 2017 and 2018 to 2019 based on year of exposure. The primary outcome was rate of inappropriate ACS exposure, defined as nonadherence to the inclusion/exclusion criteria of the ALPS trial. Secondary outcomes were rates of nonoptimal ACS exposure (delivery >7 days from ACS or term delivery). Logistic regression was used to generate adjusted odds ratios (aORs) between epochs for the primary outcome adjusting for confounders. There were 660 women who received late preterm ACS during the study period with 229 (34.6 %) deemed inappropriate exposures. The most common reason for inappropriate treatment was preterm premature rupture of membrane (PPROM; 29.0%) with exclusionary cervical examination or contraction frequency. No difference was observed in inappropriate ACS exposure between epochs (aOR = 0.83, 95% confidence interval [CI]: 0.59-1.2). However, there was a reduction in nonoptimal exposure over time (aOR = 0.67, 95% CI: 0.47-0.97) . Women receiving inappropriate ACS were more likely to deliver at term if indicated for maternal/fetal status (50.0 vs. 19.5%, p < 0.001) and preterm labor (66.0 vs. 41.9%; p = 0.015). Further, inappropriate exposure in preterm labor had higher rates of exposure latency >7 days (62.3 vs. 39.1%, p = 0.006) with a longer latency to delivery (3 vs. 16 days; p < 0.001). Over one-third of women received late preterm ACS for an indication that could be classified as indication creep. Depending on indication, inappropriate administration is associated with higher rates of nonoptimal exposure. · There is potential for indication creep of ACS administration.. · One third of late preterm ACS exposures in our study were inappropriate.. · Utilizing clinical criteria can aid in identifying patients who best benefit from late preterm ACS..

US Incidence of Late-Preterm Steroid Use and Associated Neonatal Respiratory Morbidity After Publication of the Antenatal Late Preterm Steroids Trial, 2015-2017

The Antenatal Late Preterm Steroids (ALPS) trial demonstrated a 20% reduction in the risk of respiratory complications in neonates at risk for a late-preterm birth who were exposed to antenatal corticosteroids compared with those who were not. To assess whether new evidence of steroid administration for neonatal respiratory benefit in the late-preterm period is associated with changes in obstetric practice and the use of assisted ventilation for the neonate after delivery. This cross-sectional study of US births from February 1, 2015, to October 31, 2017, as ascertained from US natality data, included live-born, singleton neonates born between 34 and 36 completed weeks of gestation to people without pregestational diabetes. An interrupted time series analysis using Poisson regression models was conducted. Data were analyzed from July 11, 2022, to November 9, 2022. Public dissemination of the ALPS trial results, which occurred during a 9-month period from February 1, 2016 (first published online), to October 31, 2016 (time of the last major professional society's guideline update in the months after the trial's publication). Steroid use, any assisted ventilation use, and assisted ventilation use for more than 6 hours immediately after the dissemination period. A total of 707 862 births were included, divided among the 12-month predissemination period (n = 250 643), dissemination period (n = 195 736), and 12-month postdissemination period (n = 261 493). Most births were at 36 weeks of gestation (53.9% in the predissemination and postdissemination period; P = .10). Small but significant differences were found between the predissemination and postdissemination period cohorts: there were more individuals 35 years or older (19.5% vs 17.9%), fewer White individuals (67.8% vs 69.8%), and more publicly insured individuals (50.5% vs 50.1%) in the postdissemination period compared with the predissemination period, respectively (P < .001 for all). Compared with what rates were expected based on the predissemination trends, the adjusted rate of steroid use increased from 5.0% to 11.7% (adjusted incidence rate ratio [IRR], 2.34; 95% CI, 2.13-2.57), and assisted ventilation use decreased from 8.9% to 8.2% (adjusted IRR, 0.91; 95% CI, 0.85-0.98) after the dissemination period. No change was observed in assisted ventilation use for more than 6 hours (adjusted IRR, 0.98; 95% CI, 0.87-1.10). These findings suggest that there was an immediate change in practice of administering antenatal steroids and a reduction in neonatal morbidity among late-preterm births associated with the dissemination of the ALPS trial, suggesting that this evidence may be translating into a reduction in immediate respiratory morbidity outside the context of a clinical trial.

Euglycemia after antenatal late preterm steroids: a multicenter, randomized controlled trial

Late preterm steroid administration can induce transient maternal and thus fetal hyperglycemia, which can increase production of fetal insulin and C-peptide. Infants delivered in this setting are subsequently at increased risk for hypoglycemia. Although maternal glycemic control before delivery is a key component of care for parturients with diabetes, this intervention has not been studied in the setting of late preterm steroid administration. This study aimed to determine the effect of maternal screening for and treatment of hyperglycemia after late preterm steroid administration on fetal C-peptide levels and other metabolic markers. This was a multicenter, randomized trial (NCT03076775) of nondiabetic parturients with a singleton gestation receiving betamethasone at 34 0/7 weeks to 36 5/7 weeks for anticipated preterm birth. Participants randomized to maternal glycemic control received fasting and 1-hour postprandial or serial intrapartum capillary blood glucose screening with insulin treatment as indicated. Those randomized to expectant management did not receive any glucose screening or treatment. The primary outcome was fetal C-peptide level measured from umbilical cord blood at delivery. Secondary outcomes included other fetal metabolic markers and neonatal hypoglycemia (glucose level <40 mg/dL). Baseline characteristics and outcomes were compared between the groups. We estimated that we would need a sample size of 144 to provide >90% power to show a 1 ng/mL decrease in C-peptide concentration (±1.5 ng/mL) at ⍺=0.05 using a 2-sample t test and 1 interim analysis. After the interim analysis, the trial was stopped for futility. Of 491 screened parturients, 163 (33%) were deemed eligible and 86 (53%) were randomized to 1 of the treatment groups (June 2017 to February 2021). One person was lost to follow-up because of delivery at another hospital. Baseline characteristics were similar between groups. The median interval from betamethasone administration to delivery was 24 hours (interquartile range, 13-96 hours) and did not differ between groups (P=.82). Most (82%) randomized to maternal glycemic control had hyperglycemia: 80% had at least 1 fasting glucose level >95 mg/dL, 75% had at least one 1-hour postprandial glucose level >140 mg/dL, and 80% had at least 1 intrapartum glucose level >110 mg/dL. In addition, 15% had at least 1 glucose level >180 mg/dL. None had maternal hypoglycemia after insulin treatment. Compared with expectant management, maternal glycemic control did not affect the median fetal C-peptide level (1.02; interquartile range, 0.52-1.85 vs 1.09; interquartile range, 0.61-1.65; P=.97) or other metabolic markers. Maternal glycemic control also did not affect neonatal hypoglycemia (49% vs 51%; P=.83) or other secondary neonatal or maternal outcomes. There was no evidence of effect modification by gestational age or body mass index at randomization, indication for betamethasone, duration from betamethasone to delivery, maternal race or ethnicity, or neonatal sex. In addition, the results were unchanged in a sensitivity analysis using a per-protocol approach. Maternal hyperglycemia was observed in most nondiabetic parturients after receiving late preterm betamethasone. However, there was no improvement in fetal metabolic status, neonatal hypoglycemia, or other neonatal or maternal outcomes with maternal glycemic control. Therefore, maternal glucose surveillance and treatment does not seem to be beneficial in nondiabetic parturients receiving late preterm steroids.

The impact of the Antenatal Late Preterm Steroids trial on the administration of antenatal corticosteroids

In 2016 the Antenatal Late Preterm Steroids study was published, demonstrating that antenatal corticosteroid therapy given to women at risk of late preterm delivery reduces respiratory morbidity in infants. However, the administration of antenatal corticosteroid therapy in late-preterm infants remains controversial. Late-preterm infants do not suffer from the same rates of morbidity as early-preterm infants, and the short-term benefits of antenatal corticosteroid therapy are less pronounced; consequently, the risk of possible harm is more difficult to balance. This study aimed to evaluate the association between the publication of the Antenatal Late Preterm Steroids study or the subsequent changes in guidelines and the rates of antenatal corticosteroid therapy administration in late-preterm infants in the United States. Data analyzed were publicly available US birth certificate data from January 1, 2016 to December 31, 2018. An interrupted time series design was used to analyze the association between publication of the Antenatal Late Preterm Steroids study and changes in monthly rates of antenatal corticosteroid administration in late preterm gestation (34+0 to 36+6 weeks). Births at 28+0 to 31+6 weeks' gestation were used as a control. Antenatal corticosteroid therapy administration in women with births at 32+0 to 34+6 weeks was explored to analyze whether the intervention influenced antenatal corticosteroid therapy administration in women in the subgroup approaching 34 weeks' gestation. Antenatal corticosteroid therapy administration in women with term births (>37 weeks' gestation) was analyzed to explore if the intervention influenced the number of term babies exposed to antenatal corticosteroid therapy. Our regression model allowed analysis of both step and slope changes. February 2016 was chosen as the intervention period. Our sample size was 18,031,950 total births. Of these, 1,056,047 were births at 34+0 to 36+6 weeks' gestation, 123,788 at 28+0 to 31+6 weeks, 153,708 at 32 to 33 weeks, and 16,602,699 were term births. There were 95,708 births at <28 weeks' gestation. There was a statistically significant increase in antenatal corticosteroid therapy administration rates in late preterm births following the online publication of the Antenatal Late Preterm Steroids study (adjusted incidence rate ratio, 1.48; 95% confidence interval, 1.36-1.61; P=.00). A significant increase in antenatal corticosteroid therapy administration rates was also seen in full-term births following the online publication of the Antenatal Late Preterm Steroids study. No significant changes were seen in antenatal corticosteroid administration rates in gestational age groups of 32+0 to 33+6 weeks or 28+0 to 31+6 weeks. Online publication of the Antenatal Late Preterm Steroids study was associated with an immediate and sustained increase in the rates of antenatal corticosteroid therapy administration in late preterm births across the United States, demonstrating a swift and successful implementation of the Antenatal Late Preterm Steroids study guidance into clinical practice. However, there is an unnecessary increase in full-term infants receiving antenatal corticosteroid therapy. Given that the long-term consequences of antenatal corticosteroid therapy are yet to be elucidated, efforts should be made to minimize the number of infants unnecessarily exposed to antenatal corticosteroid therapy.

Antenatal Steroids and Cord Blood T-cell Glucocorticoid Receptor DNA Methylation and Exon 1 Splicing.

Antenatal administration of glucocorticoids such as betamethasone (BMZ) during the late preterm period improves neonatal respiratory outcomes. However, glucocorticoids may elicit programming effects on immune function and gene regulation. Here, we test the hypothesis that exposure to antenatal BMZ alters cord blood immune cell composition in association with altered DNA methylation and alternatively expressed Exon 1 transcripts of the glucocorticoid receptor (GR) gene in cord blood CD4+ T-cells. Cord blood was collected from 51 subjects in the Antenatal Late Preterm Steroids Trial: 27 BMZ, 24 placebo. Proportions of leukocytes were compared between BMZ and placebo. In CD4+ T-cells, methylation at CpG sites in the GR promoter regions and expression of GR mRNA exon 1 variants were compared between BMZ and placebo. BMZ was associated with an increase in granulocytes (51.6% vs. 44.7% p = 0.03) and a decrease in lymphocytes (36.8% vs. 43.0% p = 0.04) as a percent of the leukocyte population vs. placebo. Neither GR methylation nor exon 1 transcript levels differed between groups. BMZ is associated with altered cord blood leukocyte proportions, although no associated alterations in GR methylation were observed.

Improving the external validity of Antenatal Late Preterm Steroids trial findings.

The external validity of randomised trials can be compromised when trial participants differ from real-world populations. In the Antenatal Late Preterm Steroids (ALPS) trial of antenatal corticosteroids at late preterm ages, participants had systematically younger gestational ages than those outside the trial setting. As risk of respiratory morbidity (the primary trial outcome) is higher at younger gestations, absolute benefits of corticosteroids calculated in the trial population may overestimate real-world treatment benefits. To estimate the real-world absolute risk reduction and number-needed-to-treat (NNT) for antenatal corticosteroids at late preterm ages, accounting for gestational age differences between the ALPS and real-world populations. Individual participant data from the ALPS trial (which recruited 2831 women with imminent preterm birth at 34+0 to 36+5weeks') was appended to population-based data for 15,741 women admitted for delivery between 34+0 and 36+5weeks' from British Columbia, Canada, 2000-2013. We used logistic regression to calculate inverse odds of sampling weights for each trial participant and re-estimated treatment effects of corticosteroids on neonatal respiratory morbidity in ALPS participants, weighted to reflect the gestational age distribution of the population-based (real-world) sample. The real-world absolute risk reduction was estimated to be -2.2 (95% CI -4.6, 0.0) cases of respiratory morbidity per 100, compared with -2.8 (95% CI -5.3, -0.3) in original trial data. Corresponding NNTs were 46 in the real-world setting vs 35 in the trial. Our focus on absolute measures also highlighted that the benefits of antenatal corticosteroids may be meaningfully greater at 34weeks vs. 36weeks (e.g., risk reductions of -3.7 vs. -1.2 per 100 respectively). The absolute risk reductions and NNTs associated with antenatal corticosteroid administration at late preterm ages estimated in our study may be more appropriate for patient counselling as they better reflect the anticipated benefits of treatment when used in a real-world situation.

Antenatal late preterm steroids: Patterns of use at a tertiary care center

Emerging concern for short- and long-term adverse outcomes of antenatal late preterm steroids (ALPS) supports the importance of appropriate patient selection and judicious application. We aimed to assess patterns of ALPS use in a tertiary care center and identify factors associated with liberal utilization.

Euglycemia after antenatal late preterm steroids (E-ALPS): a multicenter, randomized controlled trial

Late preterm steroids induce transient maternal and thus fetal hyperglycemia, which increases fetal insulin and C-peptide. Infants delivered in this setting are at increased risk for hypoglycemia. Our objective was to determine the effect of maternal screening and treatment of hyperglycemia after steroids on fetal C-peptide and metabolic markers.