Stripping/sweeping the membranes for inducing labour or preventing post-term pregnancy

Stripping or sweeping of the membranes aims to initiate labour through a cascade of physiological events. These may reduce pregnancy duration or pre-empt formal induction of labour with either oxytocin, prostaglandins or amniotomy.

The objective of this review was to assess the effects of membrane sweeping to promote or induce labour on maternal and perinatal outcomes.

We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register (last searched April 1998).

Adequately controlled trials of digital separation of the membranes from the lower uterine segment for inducing labour or for preventing post-term pregnancy, compared to either no vaginal examination or vaginal examination for cervical assessment only without the intention to detach the membranes.

Two reviewers assessed trial quality and extracted data.

Fourteen trials were included. Sweeping of the membranes, performed as a general policy in women at term, was associated with reduced duration of pregnancy and the frequency of pregnancy continuing beyond 41 weeks (relative risk 0.42, 95% confidence interval 0.19 to 0.93, random effects model) and 42 weeks. After sweeping of the membranes, there was a 17% risk reduction (confidence interval 6 to 29%, random effects model) in the use of more formal methods for labour induction. There was no difference in the mode of delivery or in the risk of infection. Discomfort during vaginal examination and other adverse effects (bleeding, irregular contractions) were more frequently reported by women allocated to sweeping.

Routine use of sweeping of membranes from 38 weeks of pregnancy onwards does not seem to produce clinically important benefits. When used as a means for induction of labour, the reduction in the use of more formal methods of induction needs to be balanced against women's discomfort and other adverse effects.