Objective: The objective was to study the effects of repeated antenatal corticosteroids on birth size, growth, and development in preterm infants.
Study design: This observational study followed up for 3 years a prospective geographic cohort in the state of Western Australia of 477 singleton infants born at <33 weeks' gestation.
Results: Birth weight ratio decreased with increasing number of corticosteroid courses (P =.001), and multivariate analyses confirmed a reduction in birth weight of as much as 9% (P =.014) and a reduction in head circumference of as much as 4% (P =.0024). There were no additional benefits in mortality or respiratory outcomes, and there was a trend toward more severe chronic lung disease. At age 3 years growth and severe disability outcomes did not appear to be related to increasing number of corticosteroid courses.
Conclusions: In this cohort study repeated corticosteroid courses were associated with adverse effects on size at birth without apparent benefits. These changes have the potential to affect later development.