Cohort study of the neonatal outcome of twin pregnancies that were treated with prophylactic or rescue antenatal corticosteroids

Objective: The purpose of this study was to compare the neonatal outcome of 2 approaches to antenatal corticosteroid therapy for threatened preterm delivery in twins: a prophylactic approach in which corticosteroids were administered every 2 weeks from 24 to 32 weeks of gestation and a rescue approach in which corticosteroids were given to women at immediate risk of preterm delivery. Study Design: A retrospective cohort study of 1038 twin babies delivered between 1990 and 1996 in a University Teaching Hospital. One hundred thirty-six babies were exposed to prophylactic therapy, and 902 babies were treated expectantly with rescue therapy. Results: Prophylactic corticosteroids were not associated with a significant reduction in respiratory distress syndrome (adjusted odds ratio, 0.7; 95% CI, 0.2-2.0). Unnecessary therapy was more likely with a prophylactic policy (relative risk, 7.5; 95% CI, 5.3-10.7) and was associated with a reduction in mean birth weight in term babies of 129 g (95% CI, -218 to -33; P = .008). Conclusion: Prophylactic corticosteroids have no proven beneficial effect on the risk of respiratory distress syndrome in preterm twin babies. Such a policy exposes a large number of babies to unnecessary treatment that adversely affects growth. (Am J Obstet Gynecol 2002;187:483-8.)