Accelerated lung maturation following maternal steroid treatment in infants born before 30 weeks gestation

A meta-analysis was performed of 9 controlled trials of maternal beta-/dexamethasone treatment in which the incidence of RDS in infants born before 30 weeks gestation was reported. A significant decrease could be shown in 250 immature infants. The number of cases was to small for analysis of lower gestational ages or for the demonstration of a reduction in mortality. In a separate study of 135 infants born before 30 weeks gestation tracheal aspirate phospholipid analysis was performed using thin layer chromatography. 64 of them had been exposed prenatally to steroids. Significantly more of these infants had a mature L/S ratio > or = 2.7 (p < 0.02) and prenatal glucocorticoid treatment was associated with a markedly increased survival rate (odds ratio 2.4, p < 0.02). We conclude from the meta-analysis of the literature and from the findings of our study, that accelerated lung maturation follows prenatal steroid treatment with a reduction in RDS-incidence even in very immature fetuses. Consequently it would be appropriate to administer glucocorticoids combined with tocolysis since this has been shown to be beneficial for those women threatening to deliver prematurely at less than 30 weeks gestation.