In small for gestational age newborn infants of toxemic mothers bioelectric brain maturation is frequently retarded and/or abnormal. The consistent abnormal EEG phenomena could — if at all — only exceptionally be explained by perinatal hypoxia or postnatal hypoglycemia and they occurred in the absence of any other overt postnatal illness. The results suggest that central nervous system maturation does not proceed independently of the nutritional status of the fetus.