Indices of fetal growth-retardation, perinatal hypoxia-related factors and childhood neurological morbidity.

Data from seven-year-old children (N = 4535) who were enrolled prenatally during the 1960s and born at term in the Boston sector of the National Collaborative Perinatal Project (NCPP) have been used to study the association of 7-year neurological morbidity with symmetric and asymmetric intrauterine growth-retardation (IUGR), head circumference at birth, and perinatal hypoxia-related factors (PHRF). In the absence of hypoxia-related factors, symmetric and asymmetric IUGR children were not at higher risk for neurological morbidity compared to non-IUGR children. In the presence of perinatal hypoxia-related factors, IUGR children were more likely to be neurologically abnormal compared to non-IUGR children, and the more severe form of IUGR (symmetric) appeared to be associated with a slightly higher risk than was the asymmetric form. Small head circumference was associated with increased risk of neurological abnormality regardless of the presence of PHRF. Potential metabolic and neurodevelopmental explanations for these findings are discussed.