The Scope of the Problem: The Epidemiology of Late Preterm and Early-Term Birth

Late preterm birth (defined as birth between 34 0/7 to 36 6/7 weeks gestation) and early-term birth (defined as birth between 37 0/7 to 38 6/7 weeks gestation) have become the topic of much recent literature and discussion as the morbidity associated with delivery at these gestational ages becomes evident. Although infants delivered during this time period remain at relatively low risk for complications, the rate of morbidities in this group, particularly as it relates to respiratory function, is increased several-fold when they are compared to infants delivered at 39 weeks. The following article reviews the morbidities and mortality associated with both late preterm and early-term birth, as well available data on long-term outcomes of neonates born at these gestational ages.