Studies of prolonged neonatal jaundice in the breast-fed infant

Abstract

The clinical course of 20 breast-fed infants with prolonged unconjugated hyperbilirubinemia is described. Severe jaundice began during the latter part of the first or beginning of the second week of life and maximum concentrations of unconjugated bilirubin in the serum ranged from 9.0 to 26.0 mg. per 100 ml. Milk from the mothers of the jaundiced infants markedly inhibited hepatic glucuronyl transferase activity in vitro. Pregnane-3(α),20(β)-diol was isolated from milk obtained from 4 mothers of infants with prolonged jaundice, but has not been isolated from normal human milk. The relationship between intensity and duration of inhibition by milk and intensity and duration of hyperbilirubinemia in the infants is illustrated. Two thirds of the breast-fed siblings of the infants studied had a history of prolonged jaundice, whereas none of the artificially fed siblings had a history of prolonged jaundice.