A longitudinal study of the intelligence and behavior of preterm and small for gestational age children.

A large sample of children (n = 850) from Dunedin, New Zealand, were classified into three groups, preterm (n = 31), small for gestational age (SGA; n = 71), and full-term, normal birth weight (n = 748). These groups were compared on intelligence measures taken at ages 3, 5, 7, and 9 years of age and parent and teacher behavior reports at 5, 7, and 9 years. The SGA group but not the preterm group had significantly lower IQ scores than the normal birth weight children. In addition, the mothers of the SGA children reported more behavior problems. These differences were not attributable to socioeconomic disadvantage in the SGA group. The results suggest "it is better to be born too early than too small."