Association between umbilical cord leptin and weight gain according to feeding type in the early postnatal period, a brief report.

BACKGROUND Weight gain in infancy depends on in utero nutritional status, with postnatal growth also dependent on feeding practices, culture, food accessibility and parents' education. OBJECTIVE To evaluate the relationship between umbilical cord blood leptin levels and feeding mode (breast-fed vs. formula) on weight gain at three months of life. MATERIAL AND METHODS Ninety-nine full-term newborns (male, n = 48; female, n = 51) were included in two groups according to feeding type: breast-fed (n = 49) and formula-fed (n = 50). Leptin was measured in blood obtained from the umbilical cord vein. RESULTS Umbilical cord leptin levels and weight gain at three months had a significant inverse correlation in formula-fed infants (r = -0.294, P = 0.038). This finding was not reflected in breast-fed infants (r = -0.212, P = 0.144). CONCLUSIONS In our Mexican breastfeeding cohort, umbilical cord leptin levels were a significant predictor of weight gain in formula-fed infants.