This report describes the effect of severe maternal hyperbilirubinemia (total bilirubin value, 40 mg/100 ml, of which about 30% to 40% was unconjugated) on the fetus for three weeks prior to delivery. The newborn at delivery had a value for cord blood unconjugated bilirubin which was similar to the maternal serum value. This phenomenon may indicate maternal to fetal transfer of unconjugated bilirubin. The newborn developed hyperbilirubinemia for which exchange transfusions were required. He also manifested Escherichia coli septicemia and expired as a result of infection. The autopsy findings revealed no evidence of bilirubin encephalopathy.