Trends and morbidity associated with oxytocin use in labour in nulliparas at term

To determine the trends in oxytocin use at a population level within New South Wales and to assess the maternal and neonatal morbidities associated with the use of oxytocin.

Trends in oxytocin use were assessed for women in NSW who were nulliparas at term with a singleton, cephalic fetus between 1998 and 2008. Maternal and neonatal morbidities were assessed in 2007-2008 using linked hospital and birth data with regression analysis. Oxytocin was also assessed by indication for use being either induction or augmentation of labour.

The overall use of oxytocin increased from 10,291 (36.5%) of births in 1998 to 14,440 (45.4%) of births in 2008 (P < 0.0001) with the increase entirely because of the increased use for induction of labour. The use of oxytocin was associated with an increase in regional analgesia (65 to 22%), instrumental delivery (21 to 18%) and caesarean section (29 to 14%) as compared to women who did not receive oxytocin in labour. Oxytocin was also associated with an increase in severe maternal adjusted odds ratios ((aOR) 1.48, 95% CI 1.30-1.68) and neonatal morbidity (aOR 1.29, 95% CI 1.17-1.41). This increase in morbidity was maintained when both augmentation and induction were assessed separately.

Oxytocin has an important role in the management of labour. However, its use should be carefully monitored with standardised treatment regimes to minimise maternal and neonatal morbidity.