摘要:Breastfeeding during infancy may have beneficial effects on various developmental outcomes in childhood. In this study, exclusively breastfed infants were randomly assigned to receive complementary foods from the age of 4 months in addition to breast milk (CF, n = 60), or to exclusively breastfeed to 6 months (EBF, n = 59). At 18 months and again at 30–35 months of age, the children were evaluated with the Parent’s Evaluation of Developmental Status questionnaire (PEDS) and the Brigance Screens-II. The parents completed the PEDS questionnaire at both time intervals and the children underwent the Brigance Screens-II at 30–35 months. At 30–35 months, no significant differences were seen in developmental scores from the Brigance screening test (p = 0.82). However, at 30–35 months a smaller percentage of parents in group CF (2%) had concerns about their children’s gross motor development compared to those in group EBF (19%; p = 0.01), which remained significant when adjusted for differences in pre-randomization characteristics (p = 0.03). No sustained effect of a longer duration of exclusive breastfeeding was seen on selected measures of developmental and behavioral status at 18 months, although at 30–35 months, a smaller percentage of parents of children introduced to complementary foods at four months of age expressed concerns about their gross motor development.