The frequency of "significant" jaundice of the newborn at this hospital increased from 8-1% of all live births in 1971 to 12-1% in 1972 and 15-4% in 1973. This coincided with an increased use of oxytocic agents and epidural anaesthetics in labour, and a change in the artificial feed given to normal infants. A retrospective study of jaundiced infants born in 1972 failed to explain the increase in jaundice. Though the use of oxytocic agents was not the direct cause, since their use results in the delivery of more infants before 40 weeks of gestation it may be a contributory factor. The use of epidural anaesthetics was sastically related to the development of jaundice but the nature of the association was not clear. Mothers of infants who became jaundiced has a significantly higher frequency of poor past obstetric histories, but once again the association was not clear. The change in artificial feeds was excluded as a possible cause.