Effectiveness of multidose antenatal steroids.

OBJECTIVE

To compare effectiveness between single and multiple courses of antenatal steroids in preterm births and determine adverse effects attributable to multiple courses.

METHODS

We studied retrospectively the neonatal outcomes of infants who weighed 1750 g or less at birth between January 1990 and December 1997. Infants exposed to a single course were compared with those exposed to two or more courses of antenatal steroids, with respect to various perinatal outcome variables.

RESULTS

Ninety-three neonates were exposed to two or more courses of antenatal steroids and 261 neonates had been given single courses. The mean (+/- standard deviation) gestational age (29.6 +/- 2.8 weeks compared with 28.7 +/- 2.7 weeks; P = .007) and birth weight (1252 +/- 321 g compared with 1159 +/- 339 g; P = .013) were significantly higher among neonates exposed to multiple courses. There were no significant differences between groups in perinatal outcomes; however, those exposed to multiple courses had a significantly lower rate of respiratory distress syndrome (RDS) (17 [18%] compared with 107 [41%]; P < or = .001) and surfactant use (40 [43%] compared with 149 [57%]; P = .02). Adjusting for confounding variables, multiple courses of steroids were significantly associated with a 65% reduction in the incidence of RDS (odds ratio 0.35; 95% confidence interval = 0.18, 0.70; P = .003).

CONCLUSION

Compared with single courses, multiple courses of antenatal steroids reduced significantly the incidence of RDS with no apparent increase in neonatal sepsis or disturbances in fetal growth.