Timing of Late Preterm Corticosteroid Administration and Neonatal Hypoglycemia

The use of antenatal corticosteroids for women at risk for preterm delivery has become widely adopted as standard of care. The American College of Obstetrics and Gynecologists (ACOG) officially recommends the use of corticosteroids for pregnant women between 24 and 34 weeks of gestation at risk of delivery within 7 days. Since publication of the ALPS trial, the Society of Maternal Fetal Medicine (SMFM) published guidelines supporting the use of late preterm steroids for singleton pregnancies between 34 weeks 0 days and 36 weeks 6 days who are at high risk of preterm birth within 7 days.

A secondary finding of the ALPS trial included the observation that the administration of antenatal betamethasone significantly increased the rate of neonatal hypoglycemia; the authors emphasized that while the long-term risks associated with neonatal hypoglycemia are not fully known, significant hypoglycemia is associated with poor neurodevelopmental outcome.

The optimal interval for administering late preterm steroids before delivery to minimize the risks of hypoglycemia while maximizing the benefits of fetal lung maturity has not been identified. The proposed research study will further investigate this question by randomizing patients to receive late preterm corticosteroids 2 days before delivery versus 7 days before delivery in order to determine if the rates and severity of neonatal hypoglycemia are different.