Influence of breast-feeding on mental and psychomotor development.

The purpose of this study was to analyze the effects of breast-feeding on cognitive and motor development. A prospective cohort study was carried out enrolling 249 babies from 2 rural and urban areas. Cognitive development was assessed at the age of 18 months. Results show that adjusted scores on the mental development index were 4.6 points higher in babies breast-fed for longer than 4 months than in those breast-fed for less time. No differences in psychomotor development were found as a function of type of feeding. A statistically-significant linear correlation was observed between the duration of breast-feeding and scores for Bayley's mental development index. These data suggest that breast-feeding for longer than 4 months has a positive effect on the baby's mental development measured at 18 months of age. Parental intelligence quotient also seems to have an influence on cognitive development.