Maternal Alcohol Use during Breast-Feeding and Infant Mental and Motor Development at One Year

Abstract The detrimental effects of maternal drinking during pregnancy on fetal health have been documented. The consequences for infants of maternal drinking during breast-feeding are unknown, but research in animals suggests that the infant could be affected by exposure to alcohol through the mother's milk. In a study of 400 infants born to members of a health maintenance organization, we investigated the relation of the mother's use of alcohol during breast-feeding to the infant's development at one year of age. Mental development, as measured by the Bayley Mental Development Index (MDI), was unrelated to maternal drinking during breast-feeding. However, motor development, as measured by the Psychomotor Development Index (PDI), was significantly lower in infants exposed regularly to alcohol in breast milk (after alcohol exposure during gestation was controlled for), with a dose–response relation (P for linear trend, 0.006). The infants of breast-feeding mothers who had at least one drink daily had a me...