Abstract
Objective: Determine whether the increased neonatal mortality following repeated courses of antenatal corticosteroids (ANCS), observed in the Thyrotropin-Releasing Hormone (TRH) Trial, was related to confounding maternal risk factors or specific preterm morbidities. Study Design: A post hoc analysis of 595 TRH trial neonates, 26 to 32 weeks' gestation, studied the association between ≥3 courses ANCS and mortality. Potential confounding maternal factors and preterm morbidities were evaluated using logistic regression and log likelihood modeling. Results: Mortality was 9.2% after ≥3 courses (13/141) vs. 4.8% after 1 or 2 courses (22/454). This association was not explained by maternal factors, or other common preterm morbidities. However, 15/141 infants receiving ≥3 courses (10.6%) had early severe lung disease (ESLD) with 10 deaths, compared to 16/454 of the 1- to 2-course infants (3.5%) with 7 deaths (odds ratio 3.5, p < 0.001). Conclusions. ESLD, but no maternal risk factors, was associated with increased mortality in preterm infants after ≥ 3 courses ANCS.