The objective of this study was to compare the outcomes at 5 years of age of SGA and AGA children born < 28 weeks of gestation. The method used was a longitudinal follow-up of a cohort of 37 dyads of SGA and AGA infants matched by gestational age (GA), gender, and date of delivery. Mean GA was 26+/-1.2 weeks, and BW was 638+/-77 g for SGA and 833+/-134 g for AGA (P < 0.0001). The SGA infants remained lighter at 3, 24, and 60 months. Their head circumference was statistically smaller at 3 and 60 months, and their length remained lower but no longer statistically significant. There was no difference after the second year of life between SGA and AGA children in the need for rehospitalization (16% versus 11%) and the incidence of medical problems such as Otitis (38% versus 41%) and asthma (24% versus 30%). SGA exhibited more neurodevelopmental deficits (41% versus 30%) and severe handicaps, including CP, blindness, deafness, and mental retardation (22% versus 14%). Those deficits were seen predominantly in association with microcephaly, which was more prevalent in the SGA group. We conclude that the combination of severe prematurity and intrauterine growth retardation constitutes a serious developmental handicap and predisposes to physical and developmental delays. The presence of microcephaly further aggravates the prognosis.