Prophylactic oxytocin for the third stage of labour

 

Abstract

Background

Complications of the third stage of labour are a significant cause of maternal mortality worldwide.

Objectives

To examine the effect of oxytocin given prophylactically in the third stage of labour on maternal and neonatal outcomes.

Search strategy

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (December 2004). We updated this search on 1 October 2009 and added the results to the awaiting classification section.

Selection criteria

Randomised or quasi-randomised controlled trials including pregnant women anticipating a vaginal delivery where oxytocin was given prophylactically for the third stage of labour.

Data collection and analysis

The review authors independently assessed trial quality and extracted data. Analysis was by intention to treat. Subgroup analyses were based on extent of selection bias, oxytocin in the context of active or expectant management of the third stage, and timing of administration. Results are presented as relative risks, and weighted mean difference, both with 95% confidence intervals using a fixed-effect model.

Main results

Fourteen trials are included.

In seven trials involving over 3000 women, prophylactic oxytocin showed benefits (reduced blood loss (relative risk (RR) for blood loss greater than 500 ml 0.50; 95% confidence interval (CI) 0.43 to 0.59) and need for therapeutic oxytocics (RR 0.50; 95% CI 0.39 to 0.64) compared to no uterotonics.

In six trials involving over 2800 women, there was little evidence of differential effects for oxytocin versus ergot alkaloids, except that oxytocin was associated with fewer manual removals of the placenta (RR 0.57; 95% CI 0.41 to 0.79), and with the suggestion of less raised blood pressure (RR 0.53; 95% CI 0.19 to 1.52) than with ergot alkaloids.

In five trials involving over 2800 women, there was little evidence of a synergistic effect of adding oxytocin to ergometrine versus ergometrine alone.

Authors' conclusions

Oxytocin appears to be beneficial for the prevention of postpartum haemorrhage. However, there is insufficient information about other outcomes and side-effects hence it is difficult to be confident about the trade-offs for these benefits. There seems little evidence in favour of ergot alkaloids alone compared to either oxytocin alone, or to ergometrine-oxytocin, but the data are sparse. More trials are needed in domiciliary deliveries in developing countries, which shoulder most of the burden of third stage complications.

[Note: The ten citations in the awaiting classification section of the review may alter the conclusions of the review once assessed.]

 

Plain language summary

Prophylactic oxytocin for the third stage of labour

Oxytocin used routinely after birth can reduce blood loss, but more research is needed on possible adverse effects.

The third stage of labour is that period from birth of the baby until delivery of the placenta. The degree of blood loss depends on how quickly the placenta separates from the uterine wall and the uterine muscle contracts. Severe blood loss - postpartum haemorrhage, is a major problem, particularly where there is poor nutrition and lack of access to treatment. The review of trials found routine use of oxytocin, a drug which helps the uterus contract, may reduce the amount of blood loss, but there is not enough evidence about adverse effects. More research is needed.