Repeat doses of prenatal corticosteroids for women at risk of preterm birth for preventing neonatal respiratory disease.

backgroundInfants born preterm are at high risk of neonatal lung disease and its sequelae. A single course of prenatal corticosteroids has not been shown to be of benefit in babies who are born more than seven days after treatment. It is not known whether there is benefit in repeating the dose of prenatal corticosteroids to women who remain at risk of preterm birth more than seven days after an initial course.

objectivesTo assess the effectiveness and safety of a repeat dose(s) of prenatal corticosteroids, given to women who remain at risk of preterm birth seven or more days after an initial course of prenatal corticosteroids. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register (January 2003), the Cochrane Controlled Trials Register (The Cochrane Library, Issue 1, 2003), MEDLINE (1965 to January 2003), EMBASE (1988 to January 2003), Current Contents (1997 to January 2003). SELECTION CRITERIA: Randomised controlled trials of women who have already received a single course of corticosteroid seven or more days previously, and who are still considered to be at risk of preterm birth; outcomes compared for women randomised to receive a repeat dose(s) of prenatal corticosteroids, with women given no further prenatal corticosteroids. DATA COLLECTION AND ANALYSIS: We assessed trial quality and extracted the data independently. MAIN

resultsFive hundred and fifty one women were recruited into the three included trials between 24 and 30 weeks' gestation. Fewer infants in the repeat dose(s) of corticosteroids group had severe lung disease compared with infants in the placebo group (relative risk (RR) 0.64, 95% confidence interval (CI) 0.44 to 0.93, 1 trial, 500 infants). No statistically significant differences were seen for any of the other primary outcomes that included other measures of respiratory morbidity, small-for-gestational-age at birth, perinatal death, periventricular haemorrhage, periventricular leucomalacia and maternal infectious morbidity. Fewer infants in the repeat dose(s) of corticosteroids group received surfactant compared with infants in the placebo group (RR 0.64, 95% CI 0.44 to 0.93, 2 trials, 537 infants). REVIEWER'S

conclusionsRepeat dose(s) of prenatal corticosteroids may reduce the severity of neonatal lung disease. However, there is insufficient evidence on the benefits and risks to recommend repeat dose(s) of prenatal corticosteroids for women at risk of preterm birth for the prevention of neonatal respiratory disease. Further trials are required.