Milk intake and feeding behavior in the first week of life and its relationship to cord blood ghrelin, leptin, and insulin concentrations.
Our aim was to study the feeding behavior of healthy term infants in the first week of life and determine whether this was related to cord blood leptin, ghrelin, and insulin. A total of 100 healthy bottle-fed infants were studied by weighing bottles of milk before and after feeds. Leptin, total ghrelin, and insulin concentrations were measured in cord blood. Mean (SD) birth weight was 3.46 (0.43) kg. Mean milk intake increased from 196.7 (83.0) g on d 1 to 585.0 (128.4) g on d 7. Milk intake over the first 6 d was significantly associated with weight gain to d 7. There was no relationship between cord ghrelin or leptin and milk intake or feed frequency. Cord blood insulin was inversely related to the mean daily number of feeds over the first 6 d (r = -0.21, p < 0.05). Birth weight and milk intake are the major determinants of weight gain in the first week of life in healthy bottle-fed infants. Total cord ghrelin and leptin are not directly related to milk intake or feed frequency in the first week of life. Circulating insulin concentrations may have a role in the initiation of feeding behavior.