Antenatal Betamethasone for Women at Risk for Late Preterm D
Antenatal glucocorticoids are widely used in obstetrics for pregnancies at risk for early preterm delivery. Their use increased especially after a consensus conference held by the National Institutes of Health in 1994, which concluded that there was strong evidence that glucocorticoids reduce adverse neonatal outcomes, including death, the respiratory distress syndrome, and other complications, when administered to women who are likely to deliver before 34 weeks of gestation.1-3 The recommendation was not extended to women at risk for preterm delivery after 34 weeks because of both a lack of data4,5 and the belief that at a threshold of 34 to 35 weeks of gestation nearly all infants thrive, with survival at this gestational age being within 1% of survival at term.6 However, it is now clear that infants who are born during the late preterm period (34 weeks 0 days to 36 weeks 6 days) have more neonatal and childhood complications than do newborns who are born at term (37 weeks or later).7-9 Because of this, a workshop in 2005 recommended redirecting research to evaluate infants who are born between 34 and 36 weeks of gestation, particularly to answer the question of whether antenatal glucocorticoids are beneficial in this population.10 Currently, 8% of all deliveries occur in the late preterm period....