Antenatal Corticosteroids

Antenatal Corticosteroids

Introduction: The National Institutes of Health issued a consensus statement in 1994 recommending the administration of antenatal corticosteroids to all patients at risk of preterm delivery before 34 weeks' gestation. This practice is widespread, but no randomized trials have estsblished the efficacy or safety of this practice. The efficacy of weekly administration of antenatal corticosteroids, compared with a single course, in decreasing the incidence of neonatal morbidity was examined, along with the potential complications of weekly treatment.

Methods: From February 1996 through April 2000, 502 pregnant women between 24 and 32 completed weeks' gestation who were at high risk of preterm delivery participated in this randomized, double-blind, placebo-controlled intention-to-treat trial conducted at 13 academic centers in the United States. A complete single cours of antenatal corticosteroids (either betamethasone, 12 mg intramuscularly repeated once in 24 hours for 2 doses, or dexamethasone, 6 mg intramuscularly repeated every 12 hours for 4 doses) was administered. Women who had not delivered 1 week after receiving the sigle cours were randomly assigned to receive either betamethasone, 12 mg intramuscularly repeated once in 24 hours for 2 doses every week until 34 weeks' gestation or delivery, whichever came first, or a similarly administered placebo (256 and 246 patients, respectively). The primary outcome measure was composite neonatal morbidity (including severe respiratory distress syndrome, bronchopulmonary dysplasia, severe intraventricular hemorrhage, periventricular leukomalacia, proven sepsis, necrotizing enterocolities, or perinatal death).

Results: Composite morbidity occurred in 22.5% of the patients who received the weekly course of antenatal corticosteroids compared with 28.0% of the single-course group (unadjusted relative risk, 0.80; 95% CI, 0.59-1.10). Group assignment and number of treatment courses were not correlated with a decrease in composite morbidity.

Conclusion: Compared with a single course of antenatal corticosteroids, weekly courses of treatment did not diminish composite neonatal morbidity. Weekly courses of antenatal corticosteroids are not recommended for women at risk of preterm delivery.