Background: Since publication of the sentinel antenatal late preterm steroids clinical trial, the use of antenatal steroids has become a routine aspect of the management of pregnancies at risk for late preterm delivery. However, in practice, the administration of antenatal corticosteroids in the late preterm period is widely varied across provider and institution, and the process of implementation of this new practice as well as outcomes associated with implementation are not well understood.
Objective: The objective was to evaluate institutional adherence to an antenatal late preterm corticosteroid protocol and to assess neonatal outcomes associated with its introduction.
Study design: This is a retrospective cohort study of all women with singleton pregnancies admitted between 34 to 36 5/7 weeks who presented in the year before ("pre-protocol": November 2012 to October 2013) and after implementation ("post-protocol": April 2016 to March 2017). The protocol recommends corticosteroid administration to women 34 to 36 5/7 weeks gestation at risk for preterm birth who have not received prior corticosteroids. Women with fetal anomalies or pregestational or gestational diabetes were excluded from analysis. The frequency with which eligible women received corticosteroids and ineligible women were appropriately excluded (adherence) was calculated on a monthly basis. Neonatal outcomes of interest were hypoglycemia, receipt of dextrose, birth weight, 5 minute Apgar less than 7, receipt of surfactant, respiratory distress syndrome, transient tachypnea of the newborn, neonatal intensive care unit length of stay, intraventricular hemorrhage, necrotizing enterocolitis, culture positive sepsis, bronchopulmonary dysplasia, and death. Bivariable and multivariable analyses were used to compare neonatal outcomes between 1) all women in the post-protocol cohort to those in the pre-protocol cohort and 2) only women who received adherent care in the post-protocol cohort to all women in the pre-protocol cohort.
Results: A total of 452 women were included in the pre-protocol cohort and 451 in the post-protocol cohort. The majority of the post-protocol women (N=366, 81.2%) received adherent care. Women in both cohorts were similar with the exception that women in the post-protocol cohort were more likely to be nulliparous (p=0.013). Compared to the pre-protocol period, neonates of women in the post-protocol period had significantly higher odds of hypoglycemia <50 mg/dL in the first 24 hours of life (aOR 1.37, 95% CI 1.05-1.80), without improvements in respiratory outcomes. Results were similar when restricting the analysis to only women in the post-protocol cohort who received care adherent care (glucose <50 mg/dL: aOR 1.52, 95% CI 1.14-2.03). No differences in composite respiratory morbidity or other neonatal outcomes were observed.
Conclusion: Uptake of a new institutional protocol for antenatal late preterm corticosteroids was rapid. Compared with historic controls, neonates exposed to antenatal late preterm corticosteroid experienced increased odds of hypoglycemia, without significant improvements in respiratory morbidities.
Keywords: antenatal late preterm steroids; corticosteroids; late preterm delivery; neonatal hypoglycemia; neonatal respiratory outcomes; protocol implementation.