Antenatal corticosteroids in late preterm infants

Current practice in the United Kingdom is to give a single course of antenatal corticosteroids to the mother if birth between 26⁺⁰ and 34⁺⁶ weeks’ gestation is a risk, with consideration given to its use between 23⁺⁰ and 25⁺⁶ weeks of pregnancy. The evidence for this comes largely from a systematic review and is supported by national guidelines.1 This systematic review of 21 studies (3885 women and 4269 infants) showed that treatment of women at risk of preterm birth with a single course of antenatal corticosteroids reduced the risk of neonatal death by 31% (95% confidence interval 19% to 42%), respiratory distress syndrome by 44% (31% to 57%), and intraventricular haemorrhage by 46% (31% to 67%).2 There is evidence that antenatal corticosteroids are used worldwide, although the gestations at which they are used varies with the availability of neonatal care.3 4 5

In the linked study (doi:10.1136/bmj.d1696), Porto and colleagues assess the effectiveness of corticosteroids for reducing respiratory disorders in infants between 34 and …