All infants born in the Puy-de-Dôme area in 1983 and referred to a neonatal care unit were studied prospectively. Children were seen at their homes at 9 months and at 2 years of age and results were compared with those found in controls. High risk groups were defined on the basis of neonatal variables including prematurity, neurologic anomalies, respiratory distress, assisted ventilation, and growth retardation. At birth, prematurity was associated with an increased risk of respiratory distress and infections were more common in small-for-dates infants. Evaluations at 9 months and at 2 years of age showed increased prevalences of growth retardation and strabismus in the high-risk infants, and neurodevelopmental tests disclosed lower performances in these children. Conversely, infectious diseases and readmissions between birth and two years of age were not increased in the high risk groups, as compared with the control group.