• Neonatology
• Neurodevelopment
• Outcomes research

Preterm births account for about 12% of deliveries in the USA and have a disproportionate impact on neonatal mortality and long-term morbidity adding to the substantial economic and emotional burden on their families and society. Late preterm (born between 34^0/7 and 36^6/7 weeks) and moderate preterm (32^0/7–33^6/7 weeks) (LMPT) births constitute >80% of the burden of prematurity and account for one-third of all neonatal intensive care admissions. LMPT births are associated with an over fourfold higher risk of neonatal mortality and 3.5 times higher risk of morbidity than their term counterparts. Severity of morbidity in survivors likely occurs along a continuum as gestational age at birth progresses from the very preterm to the late preterm infant. LMPT infants are twice as likely to have long-term neurodevelopmental disability, predominantly in the cognitive domain, compared with their term-born peers.1 Population-based studies that describe neurodevelopmental consequences following moderate and late prematurity suggest that gestational age at birth may be causally associated with the risk of adverse outcomes. However, the considerable heterogeneity in the phenotypic presentation and outcome of moderate and late preterm infants is likely a result of the complex interactions among maternal health and disease, the intrauterine fetal environment, fetal sex, number, placental health and environmental factors. Thus, gestational age at birth may merely be a trans-sectional point in the maturational trajectory of development and function of …