Outcomes of infants born near term: not quite ready for the "big wide world"?

Until recently, there has been a strongly held belief on the part of neonatal and pediatric clinicians that outcomes for infants born close to term are not different from those of babies born at full term. In the last decade, however, this assumption has been challenged by reports suggesting that this is not correct, and highlighting differences in morbidity and mortality both in the short and long term. This has led to development of new terminology to more accurately reflect the impact of immaturity associated with birth at 32-33 weeks (moderately preterm) and 34-36 weeks (late preterm) of gestation. These babies account for around 5-7% of all births and more than 75% of the preterm births in developed countries, so this new recognition of the associated increase in adverse outcomes may have a substantial impact on health care services. This review article will discuss the changing perceptions and concepts of gestational age in the preterm population, and explore the recent and emerging evidence around neonatal, early childhood, school-age, adolescent and adult outcomes for babies who are born moderately preterm and late preterm. It highlights important neonatal and childhood morbidities and will summarize associated health care, developmental and educational problems of affected children. The implications for the provision of ongoing primary and secondary health care, educational and social support to this large and heterogeneous group of individuals will be discussed.