Repeated Weekly Prenatal Corticosteroid Treatments Questioned.

2001 OCT 18 - (NewsRx.com & NewsRx.net) -- Repeated weekly injections of synthetic hormones known as corticosteroids for pregnant women at high risk of giving birth prematurely do not significantly reduce illness among newborn babies, compared with a single course of corticosteroids, researchers say.

Debra A. Guinn, MD, of the Denver Health Medical Center and the University of Colorado Health Sciences Center, Denver, and colleagues evaluated the efficacy of weekly administration of antenatal (or prenatal) corticosteroids, compared with a single course, in reducing the incidence of disease among newborn infants. The authors also evaluated potential complications of weekly treatment, according to an article in the October 3, 2001 issue of The Journal of the American Medical Association.

Corticosteroids are synthetic hormones often used to treat inflammatory illnesses, including asthma and rheumatoid arthritis. According to background information cited in the article, antenatal corticosteroid treatments administered to expectant mothers reduce the incidence of respiratory distress syndrome (RDS, a severe breathing problem that is very common in premature babies at high risk for preterm delivery), intraventricular hemorrhage (IVH, bleeding from fragile blood vessels in the brain), and mortality in premature newborn infants. While the effectiveness of a single course of coritcosteroids is well established, some doctors have given more than a single course because the duration of benefit is not known.

The authors conducted a randomized, double-blind, placebo-controlled trial in 13 academic centers in the United States from February 1996 through April 2000. A total of 502 pregnant women between 24 and 32 completed weeks gestation who were at high risk of preterm delivery took part in the study.

All patients received a complete single course of antenatal corticosteroids (either betamethasone or dexamethasone) by injection. Among participants who had not delivered one week after receiving the single course, 256 women were randomly assigned to receive betamethasone every week until 34 weeks' gestation or delivery, whichever came first. A similarly administered placebo was assigned to 246 other women.

The authors measured a composite of diseases that often affect very premature newborns, including severe RDS, bronchopulmonary dysplasia (a lung disorder that may affect babies who require extensive oxygen therapy or ventilator support), severe IVH, periventricular leukomalacia (damage and softening of the white matter in the inner part of the brain), proven sepsis (a serious infection caused by bacteria in the body or bloodstream that can lead to shock), necrotizing enterocolitis (severe intestinal inflammation), or perinatal death.

"In the single-course group, the rate of composite morbidity was 28.0%, compared with 22.5% of neonates in the weekly course group," the authors write. The difference was not statistically significant. "Neither group assignment nor ...