Abstract 1048 Poster Session I, Saturday, 5/1 (poster 52)

Antenatal steroid therapy has been shown to significantly decrease the incidence of Respiratory Distress Syndrome (RDS), Intraventricular Hemorrhage (IVH) and neonatal mortality in preterm infants. A single course is now standard of care. However, some clinicians give weekly repeated doses (12mg IM × 2, followed by 12mg IM weekly). Safety and efficacy of repeated courses has not been fully investigated specifically for very low birth weight infants. To determine if one course plus serial weekly doses is associated with additional benefit or adverse outcome as compared to a single course, we reviewed the clinical courses of 81 less than 28 week singleton infants who were exposed to antenatal steroids (BW 880 ± 234 SD, range 461 to 1455gms GA 26.2 ± 1.5 SD, range 23-28 wks). Chi square for linear trend and logistic regression controlling for GA was used to evaluate the dose response effect. 35 infants with BW 903 ± 219gms and GA 26.5 ± 1.4 wks were exposed to a single course and 46 infants with BW 862 ± 246 gms and GA 26.0 ± 1.5 wks were exposed to 2 to 6 serial courses. The 2 groups had similar BW, GA, sex and race distribution. The serial steroid group, as compared to single course group had significantly decreased incidence of RDS (33.3% vs 54.3%, p<0.05) and PDA (13.6% vs 34.6%, p<0.03). Incidence of BPD (29.6% vs 43.2%), IVH grade 3-4 (2.5% vs 3.7%), sepsis (14.8% vs 12.3%), NEC (9.9% vs 8.6%), ROP (15% vs 25%), and mortality (2.5% vs 3.7%) were similar between the two groups. Birthweight and head circumference at birth (23.5 ± 1.5cm vs 23.6 ± 2.4cm) corrected for gestation, and the % of infants with less than 10th percentile BW and HC were similar. Steroid treated mothers had similar incidence of chorioamnioitis (29.6% vs 32.1%) and post partum endometritis (2.5% vs 3.7%).

Conclusion: Repeated courses of antenatal corticosteroids during pregnancy as compared to a single course may reduce the risk of RDS in VLBW neonates without increasing maternal or neonatal complications. Prospective randomized clinical trials are needed to determine the optimal number of courses and retreatment intervals.