Prostaglandins for preventing postpartum haemorrhage

An injectable uterotonic is the drug of choice for routine third stage management when the placenta is delivered. Oral or sublingual misoprostol may be used where no injectable uterotonic is available.

After her baby is born, the woman's womb (uterus) contracts and bleeding decreases. If the womb does not contract, postpartum haemorrhage (heavy bleeding) can occur, which can be life threatening. A prostaglandin, oxytocin and ergometrine are all drugs that cause contractions of the womb (uterotonics). This review of 72 randomised controlled trials, involving 52,678 women, found that oral or sublingual prostaglandin (misoprostol) is effective in reducing severe haemorrhage after giving birth and the need for blood transfusions. Misoprostol is not as effective as oxytocin and has more side-effects. The main side-effects are shivering, high temperature and diarrhoea, occurring in a significant proportion of women. Twenty-six of the trials included centres in low- and middle-income countries only. Misoprostol may be useful in places where injectable uterotonics are not available, perhaps because of poor access to skilled healthcare providers. Injectable prostaglandin may be effective in reducing blood loss but has adverse effects of vomiting, abdominal pain and diarrhoea and costs more.

Authors' conclusions: 

Oral or sublingual misoprostol shows promising results when compared with placebo in reducing blood loss after delivery. The margin of benefit may be affected by whether other components of the management of the third stage of labour are used or not. As side-effects are dose-related, research should be directed towards establishing the lowest effective dose for routine use, and the optimal route of administration.

Neither intramuscular prostaglandins nor misoprostol are preferable to conventional injectable uterotonics as part of the management of the third stage of labour especially for low-risk women; however, evidence has been building for the use of oral misoprostol to be effective and safe in areas with low access to facilities and skilled healthcare providers and future research on misoprostol use in the community should focus on implementation issues.

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Background: 

Prostaglandins have mainly been used for postpartum haemorrhage (PPH) when other measures fail. Misoprostol, a new and inexpensive prostaglandin E1 analogue, has been suggested as an alternative for routine management of the third stage of labour.

Objectives: 

To assess the effects of prophylactic prostaglandin use in the third stage of labour.

Search strategy: 

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (7 January 2011). We updated this search on 25 May 2012 and added the results to the awaiting classification section.

Selection criteria: 

Randomised trials comparing a prostaglandin agent with another uterotonic or no prophylactic uterotonic (nothing or placebo) as part of management of the third stage of labour. The primary outcomes were blood loss 1000 mL or more and the use of additional uterotonics.

Data collection and analysis: 

Two review authors independently assessed eligibility and trial quality and extracted data.

Main results: 

We included 72 trials (52,678 women). Oral or sublingual misoprostol compared with placebo is effective in reducing severe PPH (oral: seven trials, 6225 women, not totalled due to significant heterogeneity; sublingual: risk ratio (RR) 0.66; 95% confidence interval (CI) 0.45 to 0.98; one trial, 661 women) and blood transfusion (oral: RR 0.31; 95% CI 0.10 to 0.94; four trials, 3519 women).

Compared with conventional injectable uterotonics, oral misoprostol was associated with higher risk of severe PPH (RR 1.33; 95% CI 1.16 to 1.52; 17 trials, 29,797 women) and use of additional uterotonics, but with a trend to fewer blood transfusions (RR 0.84; 95% CI 0.66 to 1.06; 15 trials; 28,213 women). Additional uterotonic data were not totalled due to heterogeneity. Misoprostol use is associated with significant increases in shivering and a temperature of 38º Celsius compared with both placebo and other uterotonics.