Neonatal hyperbilirubinaemia following the use of oxytocin in labour.

A prospective study of 1353 labours and the relevant newborn failed to reveal any significant difference between the incidence of neonatal hyperbilirubinaemia (defined as a level of 12 mg. or more per 100 ml.) following spontaneous labour, and after labour induced or accelerated by oxytocin. The incidence of unexplained neonatal hyperbilirubinaemia after spontaneous labour was 6-3 per cent. Following induced labour however there was a highly significant (P less than 0-001) association between the mean total dose of oxytocin used for induction and the incidence of neonatal hyperbilirubinaemia. The proportion of babies who developed hyperbilirubinaemia increased in direct relation to the total dose of oxytocin used for the induction. In this series the incidence of hyperbilirubinaemia increased sharply when the total dose of oxytocin exceeded 20 units as it did hyperbilirubinaemia and birthweight, or duration of spontaneous labour. When labour was induced, however, the proportion on newborn babies with hyperbilirubinaemia increased with the duration of labour. The significance of these findings is discussed.