Jaundice in full term healthy neonates--a population study.

A geographically based population of 498 full term, appropriate for gestational age, healthy, singleton neonates was used to study the effect of obstetric and nursery practices on the occurrence of neonatal jaundice. At 3-4 days 56% of babies became visibly jaundiced (plasma bilirubin (PB) greater than 100 mumol/l) and 10% were hyperbilirubinaemic (PB greater than 200 mumol/l). Less mature babies, those slow to pass meconium and those who had lost weight at 4 and 7 days were more likely to be jaundiced. Obstetric practices, drugs given during labour, mother's or baby's blood group, natural illumination, plethora, extravasated blood or mode of feeding were found to have no effect. No benefit from giving supplementary milk or dextrose to breast fed babies was discovered. At 6-7 days at least 9% of babies, all but one of whom were breast fed, were visibly jaundiced. The frequency of prolonged jaundice (breast milk jaundice) was 3.8% of breast fed babies at 3 weeks and zero by 7 weeks. The proportion of babies receiving phototherapy was 2.2%.