Determinants of neonatal hypoglycemia after antenatal administration of corticosteroids (ACS) for lung maturation: Data from two referral centers and review of the literature

Background: A correlation between ACS and neonatal hypoglycemia has been recently demonstrated. Aims: The aim of the study was to evaluate the determinants of neonatal hypoglycemia in women exposed to ACS for respiratory distress syndrome prevention. Material and methods: Retrospective, multicenter, cohort study conducted in two Tertiary University Units. All fetuses delivered from 2016 to 2017 after ACS (two doses i.m. of Betamethasone 12 mg 24 h apart) were considered eligible for the study purpose. The primary outcome was the incidence of hypoglycemia, defined as a glycemic value <= 45 mg/dl within the first 48 h of neonatal life. The effect on neonatal glycaemia due to timing (interval from exposure to delivery) and type (single completed, single partial or repeated course) of ACS administration was also assessed. Results: Overall, 99 neonates met the inclusion criteria. Hypoglycemia occurred in 38/99 (38.4%) of the included newborns. Compared to normoglycemic neonates, those with hypoglycemia had lower gestational age at delivery (33.06 +/- 3.37 vs. 35.94 +/- 3.17 g; p < 0.0001). Lower birthweight (1747.28 +/- 815.29 vs. 2499.24 +/- 780.51 g; p < 0.0001), a shorter interval time from administration to delivery (1.85 +/- 2.59 vs. 3.34 +/- 3.39 weeks; p = 0.02) and a higher incidence of single partial course (23.7 vs. 8.72%; p = 0.03). Multivariate logistic regression found that only birthweight was significantly associated with neonatal hypoglycemia (OR 0.4 95% CI -1.16/-0.04; p < 0.038). Conclusion: Hypoglycemia occurs in a large proportion of fetuses exposed to ACS independently from the type of exposure (single partial/single completed) and from the time interval between ACS administration and delivery. Birthweight seems to be the strongest determinant for the occurrence neonatal hypoglycemia after antenatal administration of steroids for lung maturation.