Continuation versus discontinuation of oxytocin infusion during the active phase of labour: a randomised controlled trial.

Abstract

To investigate whether discontinuation of oxytocin infusion increases the duration of the active phase of labour and reduces maternal and neonatal complications. Randomised controlled trial. Department of Obstetrics and Gynaecology, Regional Hospital of Randers, Denmark. Women with singleton pregnancy in the vertex position undergoing labour induction or augmentation. Two hundred women were randomised when cervical dilation was ≤4cm to either continue or discontinue oxytocin infusion when cervical dilation reached 5cm. The primary outcome was duration of the active phase of labour, defined as the time period from 5cm of cervical dilation until delivery. Secondary outcomes were mode of delivery, uterine tachysystole, hyperstimulation, abnormalities in fetal heart rate, postpartum haemorrhage rate, perineal tears, and neonatal outcomes. The active phase of labour was longer by 41minutes (95% confidence interval 11-75minutes) in the discontinued group (median 125minutes in 85 women who had reached the active phase and delivered vaginally) versus the continued group (median 88minutes in 78 women). The incidence of fetal heart rate abnormalities (51 versus 20%) and uterine hyperstimulation (12 versus 2%) was significantly greater in the continued than the discontinued oxytocin group. The incidence of tachysystole, caesarean deliveries, postpartum haemorrhage, third degree perineal tears and adverse neonatal outcomes was higher in the continued group, but did not reach significance. Discontinuation of oxytocin infusion in the active phase of labour may improve some labour outcomes but has the disadvantage of increasing the duration of the active phase of labour. Stopping oxytocin in the active phase seems to make labour less complicated but lengthens duration.