Latency of late preterm steroid administration to delivery and risk of neonatal hypoglycemia

Antenatal corticosteroids: an updated assessment of anticipated benefits and potential risks

Antenatal steroid therapy is increasingly central to the obstetrical management of women at imminent risk of preterm birth. For women likely to deliver between 24 and 34 weeks' gestation, antenatal steroid therapy is the standard of care, conferring sizable benefits and few risks in high-resource environments when appropriately targeted. Recent studies have focused on antenatal steroid use in periviable and late preterm populations, and in term cesarean deliveries. As a result, antenatal steroid therapy has now been applied from 22 to 39+6 weeks of estimated gestational age. There is also an increased appreciation that the vast majority of randomized control data informing the use of antenatal steroids are derived from predominantly high-resource, White populations. Accordingly, a sizable amount of work has recently been undertaken to test how to safely use antenatal steroids in low- and middle-resource environments, wherein the often high rates of preterm birth make these low-cost, easily administered interventions an attractive proposition. It is likely underappreciated by the obstetrical and neonatal communities that the overall efficacy of antenatal steroid therapy is highly variable (including when preterm risk is accurately assessed), the treatment regimens used are largely arbitrary, dosing is suprapharmacologic for effect, and the benefit-risk balance is significantly and differentially modified by gestation. It is also very likely that the patients consenting to receive these treatments are similarly unaware of the complex balance of potential benefits and harms. Although a small number of follow-up studies present a generally benign picture of long-term antenatal steroid risk, several large, population-based retrospective studies have identified associations between antenatal steroid use, childhood mental disease, and newborn infections that warrant urgent attention. Of particular contemporary importance are emergent efforts to optimize antenatal steroid regimens on the basis of the pharmacokinetics and pharmacodynamics of the agents themselves, the need for better targeting of these potent drugs, and clear articulation of the potential benefits and harms of antenatal steroid use at differing stages of pregnancy and in different delivery contexts.

The contribution of hypertensive disorders of pregnancy to late preterm and term admissions to neonatal units in the UK 2012-2020 and opportunities to avoid admission: A population-based study using the National Neonatal Research Database

OBJECTIVE

To quantify maternal hypertensive disorder of pregnancy (HDP) prevalence in late preterm and term infants admitted to neonatal units (NNU) and assess opportunities to avoid admissions.

DESIGN

A retrospective population-based study using the National Neonatal Research Database.

SETTING

England and Wales.

POPULATION

Infants born ≥34 weeks' gestation admitted to NNU between 2012 and 2020.

METHODS

Outcomes in HDP infants are compared with non-HDP infants using regression models.

MAIN OUTCOME MEASURES

Hypertensive disorder of pregnancy, primary reason for admission, clinical diagnoses and resource use.

RESULTS

16 059/136 220 (11.8%) of late preterm (34+0 to 36+6 weeks' gestation) and 14 885/284 646 (5.2%) of term (≥37 weeks' gestation) admitted infants were exposed to maternal HDP. The most common primary reasons for HDP infant admission were respiratory disease (28.3%), prematurity (22.7%) and hypoglycaemia (16.4%). HDP infants were more likely to be admitted with primary hypoglycaemia than were non-HDP infants (odds ratio [OR] 2.1, 95% confidence interval [CI] 2.0-2.2, P < 0.0001). 64.5% of HDP infants received i.v. dextrose. 35.7% received mechanical or non-invasive ventilation. 8260/30 944 (26.7%) of HDP infants received intervention for hypoglycaemia alone (i.v. dextrose) with no other major intervention (respiratory support, parenteral nutrition, central line, arterial line or blood transfusion).

CONCLUSIONS

The burden of maternal HDP on late preterm and term admissions to NNU is high, with hypoglycaemia and respiratory disease being the main drivers for admission. Over one in four were admitted solely for management of hypoglycaemia. Further research should determine whether maternal antihypertensive agent choice or postnatal pathways may reduce NNU admission.

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

BACKGROUND

In 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.

METHODS

This 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.

RESULTS

Among 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).

CONCLUSIONS

Exposure 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.