Antenatal corticosteroid therapy for fetal maturation.

OBJECTIVES: To assess the benefits and risks of antenatal corticosteroid therapy for fetal maturation.

OPTIONS: To administer antenatal corticosteroids or not to women at risk of preterm birth.

OUTCOMES: Perinatal morbidity, including: respiratory distress syndrome, intraventricular hemorrhage, infection, adrenal suppression, somatic and brain growth; perinatal mortality; and maternal morbidity, including infection and adrenal suppression.

EVIDENCE: MEDLINE and PubMed searches 1996 to August 2002 for English-language articles related to antenatal corticosteroid therapy for fetal maturation, the Cochrane Library, and national statements including that of the National Institutes of Health (NIH), the American College of Obstetricians and Gynecologists, and the Royal College of Obstetricians and Gynaecologists.

VALUES: The evidence obtained was reviewed and evaluated by the Maternal-Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and recommendations were made according to guidelines developed by the Canadian Task Force on the Periodic Health Exam. BENEFITS AND HARMS: A single course of corticosteroids reduces perinatal mortality, respiratory distress syndrome, and intraventricular hemorrhage. Information regarding repeat courses of corticosteroids is limited and conflicting, with many studies being retrospective and non-randomized. Some studies suggested a reduction in respiratory distress syndrome with repeat courses, but some found increased rates of neonatal and maternal infection; fetal, neonatal, and maternal adrenal suppression; decreased fetal or neonatal somatic and brain growth; and increased perinatal mortality.

RECOMMENDATIONS: The SOGC supports the recommendations of the NIH Consensus Development Panel: 1. All pregnant women between 24 and 34 weeks' gestation who are at risk of preterm delivery within 7 days should be considered candidates for antenatal treatment with a single course of corticosteroids. (I-A) 2. Treatment should consist of two 12 mg doses of betamethasone given IM 24 hours apart, or four 6 mg doses of dexamethasone given IM 12 hours apart (I-A). There is no proof of efficacy for any other regimen. 3. Because of insufficient scientific data from randomized clinical trials regarding efficacy and safety, repeat courses of corticosteroids should not be used routinely (II-2E) but be reserved for women participating in randomized controlled trials.

VALIDATION: This Committee Opinion has been reviewed and approved by the Maternal-Fetal Medicine Committee of the SOGC and approved by SOGC Council.