Jaundice in the full-term neonate.

Hyperbilirubinemia is the most common problem experienced by the full-term infant in the immediate neonatal period. The development of jaundice was prospectively investigated in 866 newborns. Significant correlations were found between the serum bilirubin level and the method of birth, perinatal complications, blood group incompatibilities, birth weight, and method of feeding. Breast-feeding was highly related to the development of exaggerated jaundice. The most common occurrence of jaundice requiring phototherapy was in breast-feeding infants in whom no cause for the jaundice could be determined. Study findings were most compatible with a theory of relative caloric deprivation as an explanation of the increased incidence of hyperbilirubinemia found in breast-fed newborns.