Oral misoprostol versus injectable methylergometrine in management of the third stage of labor

Uterotonic drugs to prevent postpartum haemorrhage: a network meta-analysis

BACKGROUND

Postpartum haemorrhage (PPH) is the leading cause of maternal mortality worldwide. Prophylactic uterotonic drugs can reduce blood loss and are routinely recommended. There are several uterotonic drugs for preventing PPH, but it is still debatable which drug or combination of drugs is the most effective.

OBJECTIVES

To identify the most effective and cost-effective uterotonic drug(s) to prevent PPH, and generate a ranking according to their effectiveness and side-effect profile.

METHODS

The Cochrane Pregnancy and Childbirth's Trials Register (1 June 2015), ClinicalTrials.gov and the World Health Organization (WHO)'s International Clinical Trials Registry Platform (ICTRP) were searched for unpublished trial reports (30 June 2015). In addition, reference lists of retrieved studies (updated October 2017) were searched for randomised trials evaluating uterotonic drugs for preventing PPH. The study estimated relative effects and rankings for preventing PPH, defined as blood loss of ≥ 500 ml and ≥ 1000 ml. Pairwise meta-analyses and network meta-analysis were performed to determine the relative effects and rankings of all available drugs and combinations thereof [ergometrine, misoprostol (Cytotec^®; Pfizer Inc., New York, NY, USA), misoprostol plus oxytocin (Syntocinon^®; Novartis International AG, Basel, Switzerland), carbetocin (Pabal^®; Ferring Pharmaceuticals, Saint-Prex, Switzerland), ergometrine plus oxytocin (Syntometrine^®; Alliance Pharma plc, Chippenham, UK), oxytocin, and a placebo or no treatment]. Primary outcomes were stratified according to the mode of birth, prior risk of PPH, health-care setting, drug dosage, regimen and route of drug administration. Sensitivity analyses were performed according to study quality and funding source, among others. A model-based economic evaluation compared the relative cost-effectiveness separately for vaginal births and caesareans with or without including side effects.

RESULTS

From 137 randomised trials and 87,466 women, ergometrine plus oxytocin, carbetocin and misoprostol plus oxytocin were found to reduce the risk of PPH blood loss of ≥ 500 ml compared with the standard drug, oxytocin [ergometrine plus oxytocin: risk ratio (RR) 0.69, 95% confidence interval (CI) 0.57 to 0.83; carbetocin: RR 0.72, 95% CI 0.52 to 1.00; misoprostol plus oxytocin: RR 0.73, 95% CI 0.6 to 0.9]. Each of these three strategies had 100% cumulative probability of being ranked first, second or third most effective. Oxytocin was ranked fourth, with an almost 0% cumulative probability of being ranked in the top three. Similar rankings were noted for the reduction of PPH blood loss of ≥ 1000 ml (ergometrine plus oxytocin: RR 0.77, 95% CI 0.61 to 0.95; carbetocin: RR 0.70, 95% CI 0.38 to 1.28; misoprostol plus oxytocin: RR 0.90, 95% CI 0.72 to 1.14), and most secondary outcomes. Ergometrine plus oxytocin and misoprostol plus oxytocin had the poorest ranking for side effects. Carbetocin had a favourable side-effect profile, which was similar to oxytocin. However, the analysis was restricted to high-quality studies, carbetocin lost its ranking and was comparable to oxytocin. The relative cost-effectiveness of the alternative strategies is inconclusive, and the results are affected by both the uncertainty and inconsistency in the data reported on adverse events. For vaginal delivery, when assuming no adverse events, ergometrine plus oxytocin is less costly and more effective than all strategies except carbetocin. The strategy of carbetocin is both more effective and more costly than all other strategies. When taking adverse events into consideration, all prevention strategies, except oxytocin, are more costly and less effective than carbetocin. For delivery by caesarean section, with and without adverse events, the relative cost-effectiveness is different, again because of the uncertainty in the available data.

LIMITATIONS

There was considerable uncertainty in findings within the planned subgroup analyses, and subgroup effects cannot be ruled out.

CONCLUSIONS

Ergometrine plus oxytocin, carbetocin and misoprostol plus oxytocin are more effective uterotonic drug strategies for preventing PPH than the current standard, oxytocin. Ergometrine plus oxytocin and misoprostol plus oxytocin cause significant side effects. Carbetocin has a favourable side-effect profile, which was similar to oxytocin. However, most carbetocin trials are small and of poor quality. There is a need for a large high-quality trial comparing carbetocin with oxytocin; such a trial is currently being conducted by the WHO. The relative cost-effectiveness is inconclusive, and results are affected by uncertainty and inconsistency in adverse events data.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42015020005; Cochrane Pregnancy and Childbirth Group (substudy) reference number 0871; PROSPERO-Cochrane (substudy) reference number CRD42015026568; and sponsor reference number ERN_13-1414 (University of Birmingham, Birmingham, UK).

FUNDING

Funding for this study was provided by the National Institute for Health Research Health Technology Assessment programme in a research award to the University of Birmingham and supported by the UK charity Ammalife (UK-registered charity 1120236). The funders of the study had no role in study design, data collection, data synthesis, interpretation or writing of the report.

Uterotonic agents for preventing postpartum haemorrhage: a network meta-analysis

BACKGROUND

Postpartum haemorrhage (PPH) is the leading cause of maternal mortality worldwide. Prophylactic uterotonic agents can prevent PPH, and are routinely recommended. The current World Health Organization (WHO) recommendation for preventing PPH is 10 IU (international units) of intramuscular or intravenous oxytocin. There are several uterotonic agents for preventing PPH but there is still uncertainty about which agent is most effective with the least side effects. This is an update of a Cochrane Review which was first published in April 2018 and was updated to incorporate results from a recent large WHO trial.

OBJECTIVES

To identify the most effective uterotonic agent(s) to prevent PPH with the least side effects, and generate a ranking according to their effectiveness and side-effect profile.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (24 May 2018), and reference lists of retrieved studies.

SELECTION CRITERIA

All randomised controlled trials or cluster-randomised trials comparing the effectiveness and side effects of uterotonic agents with other uterotonic agents, placebo or no treatment for preventing PPH were eligible for inclusion. Quasi-randomised trials were excluded. Randomised trials published only as abstracts were eligible if sufficient information could be retrieved.

DATA COLLECTION AND ANALYSIS

At least three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We estimated the relative effects and rankings for preventing PPH ≥ 500 mL and PPH ≥ 1000 mL as primary outcomes. Secondary outcomes included blood loss and related outcomes, morbidity outcomes, maternal well-being and satisfaction and side effects. Primary outcomes were also reported for pre-specified subgroups, stratifying by mode of birth, prior risk of PPH, healthcare setting, dosage, regimen and route of administration. We performed pairwise meta-analyses and network meta-analysis to determine the relative effects and rankings of all available agents.

MAIN RESULTS

The network meta-analysis included 196 trials (135,559 women) involving seven uterotonic agents and placebo or no treatment, conducted across 53 countries (including high-, middle- and low-income countries). Most trials were performed in a hospital setting (187/196, 95.4%) with women undergoing a vaginal birth (71.5%, 140/196).Relative effects from the network meta-analysis suggested that all agents were effective for preventing PPH ≥ 500 mL when compared with placebo or no treatment. The three highest ranked uterotonic agents for prevention of PPH ≥ 500 mL were ergometrine plus oxytocin combination, misoprostol plus oxytocin combination and carbetocin. There is evidence that ergometrine plus oxytocin (RR 0.70, 95% CI 0.59 to 0.84, moderate certainty), carbetocin (RR 0.72, 95% CI 0.56 to 0.93, moderate certainty) and misoprostol plus oxytocin (RR 0.70, 95% CI 0.58 to 0.86, low certainty) may reduce PPH ≥ 500 mL compared with oxytocin. Low-certainty evidence suggests that misoprostol, injectable prostaglandins, and ergometrine may make little or no difference to this outcome compared with oxytocin.All agents except ergometrine and injectable prostaglandins were effective for preventing PPH ≥ 1000 mL when compared with placebo or no treatment. High-certainty evidence suggests that ergometrine plus oxytocin (RR 0.83, 95% CI 0.66 to 1.03) and misoprostol plus oxytocin (RR 0.88, 95% CI 0.70 to 1.11) make little or no difference in the outcome of PPH ≥ 1000 mL compared with oxytocin. Low-certainty evidence suggests that ergometrine may make little or no difference to this outcome compared with oxytocin meanwhile the evidence on carbetocin was of very low certainty. High-certainty evidence suggests that misoprostol is less effective in preventing PPH ≥ 1000 mL when compared with oxytocin (RR 1.19, 95% CI 1.01 to 1.42). Despite the comparable relative treatment effects between all uterotonics (except misoprostol) and oxytocin, ergometrine plus oxytocin, misoprostol plus oxytocin combinations and carbetocin were the highest ranked agents for PPH ≥ 1000 mL.Misoprostol plus oxytocin reduces the use of additional uterotonics (RR 0.56, 95% CI 0.42 to 0.73, high certainty) and probably also reduces the risk of blood transfusion (RR 0.51, 95% CI 0.37 to 0.70, moderate certainty) when compared with oxytocin. Carbetocin, injectable prostaglandins and ergometrine plus oxytocin may also reduce the use of additional uterotonics but the certainty of the evidence is low. No meaningful differences could be detected between all agents for maternal deaths or severe morbidity as these outcomes were rare in the included randomised trials where they were reported.The two combination regimens were associated with important side effects. When compared with oxytocin, misoprostol plus oxytocin combination increases the likelihood of vomiting (RR 2.11, 95% CI 1.39 to 3.18, high certainty) and fever (RR 3.14, 95% CI 2.20 to 4.49, moderate certainty). Ergometrine plus oxytocin increases the likelihood of vomiting (RR 2.93, 95% CI 2.08 to 4.13, moderate certainty) and may make little or no difference to the risk of hypertension, however absolute effects varied considerably and the certainty of the evidence was low for this outcome.Subgroup analyses did not reveal important subgroup differences by mode of birth (caesarean versus vaginal birth), setting (hospital versus community), risk of PPH (high versus low risk for PPH), dose of misoprostol (≥ 600 mcg versus < 600 mcg) and regimen of oxytocin (bolus versus bolus plus infusion versus infusion only).

AUTHORS' CONCLUSIONS

All agents were generally effective for preventing PPH when compared with placebo or no treatment. Ergometrine plus oxytocin combination, carbetocin, and misoprostol plus oxytocin combination may have some additional desirable effects compared with the current standard oxytocin. The two combination regimens, however, are associated with significant side effects. Carbetocin may be more effective than oxytocin for some outcomes without an increase in side effects.

Uterotonic agents for preventing postpartum haemorrhage: a network meta-analysis

BACKGROUND

Postpartum haemorrhage (PPH) is the leading cause of maternal mortality worldwide. Prophylactic uterotonic drugs can prevent PPH, and are routinely recommended. There are several uterotonic drugs for preventing PPH but it is still debatable which drug is best.

OBJECTIVES

To identify the most effective uterotonic drug(s) to prevent PPH, and generate a ranking according to their effectiveness and side-effect profile.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (1 June 2015), ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) for unpublished trial reports (30 June 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

All randomised controlled comparisons or cluster trials of effectiveness or side-effects of uterotonic drugs for preventing PPH.Quasi-randomised trials and cross-over trials are not eligible for inclusion in this review.

DATA COLLECTION AND ANALYSIS

At least three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We estimated the relative effects and rankings for preventing PPH ≥ 500 mL and PPH ≥ 1000 mL as primary outcomes. We performed pairwise meta-analyses and network meta-analysis to determine the relative effects and rankings of all available drugs. We stratified our primary outcomes according to mode of birth, prior risk of PPH, healthcare setting, dosage, regimen and route of drug administration, to detect subgroup effects.The absolute risks in the oxytocin are based on meta-analyses of proportions from the studies included in this review and the risks in the intervention groups were based on the assumed risk in the oxytocin group and the relative effects of the interventions.

MAIN RESULTS

This network meta-analysis included 140 randomised trials with data from 88,947 women. There are two large ongoing studies. The trials were mostly carried out in hospital settings and recruited women who were predominantly more than 37 weeks of gestation having a vaginal birth. The majority of trials were assessed to have uncertain risk of bias due to poor reporting of study design. This primarily impacted on our confidence in comparisons involving carbetocin trials more than other uterotonics.The three most effective drugs for prevention of PPH ≥ 500 mL were ergometrine plus oxytocin combination, carbetocin, and misoprostol plus oxytocin combination. These three options were more effective at preventing PPH ≥ 500 mL compared with oxytocin, the drug currently recommended by the WHO (ergometrine plus oxytocin risk ratio (RR) 0.69 (95% confidence interval (CI) 0.57 to 0.83), moderate-quality evidence; carbetocin RR 0.72 (95% CI 0.52 to 1.00), very low-quality evidence; misoprostol plus oxytocin RR 0.73 (95% CI 0.60 to 0.90), moderate-quality evidence). Based on these results, about 10.5% women given oxytocin would experience a PPH of ≥ 500 mL compared with 7.2% given ergometrine plus oxytocin combination, 7.6% given carbetocin, and 7.7% given misoprostol plus oxytocin. Oxytocin was ranked fourth with close to 0% cumulative probability of being ranked in the top three for PPH ≥ 500 mL.The outcomes and rankings for the outcome of PPH ≥ 1000 mL were similar to those of PPH ≥ 500 mL. with the evidence for ergometrine plus oxytocin combination being more effective than oxytocin (RR 0.77 (95% CI 0.61 to 0.95), high-quality evidence) being more certain than that for carbetocin (RR 0.70 (95% CI 0.38 to 1.28), low-quality evidence), or misoprostol plus oxytocin combination (RR 0.90 (95% CI 0.72 to 1.14), moderate-quality evidence)There were no meaningful differences between all drugs for maternal deaths or severe morbidity as these outcomes were so rare in the included randomised trials.Two combination regimens had the poorest rankings for side-effects. Specifically, the ergometrine plus oxytocin combination had the higher risk for vomiting (RR 3.10 (95% CI 2.11 to 4.56), high-quality evidence; 1.9% versus 0.6%) and hypertension [RR 1.77 (95% CI 0.55 to 5.66), low-quality evidence; 1.2% versus 0.7%), while the misoprostol plus oxytocin combination had the higher risk for fever (RR 3.18 (95% CI 2.22 to 4.55), moderate-quality evidence; 11.4% versus 3.6%) when compared with oxytocin. Carbetocin had similar risk for side-effects compared with oxytocin although the quality evidence was very low for vomiting and for fever, and was low for hypertension.

AUTHORS' CONCLUSIONS

Ergometrine plus oxytocin combination, carbetocin, and misoprostol plus oxytocin combination were more effective for preventing PPH ≥ 500 mL than the current standard oxytocin. Ergometrine plus oxytocin combination was more effective for preventing PPH ≥ 1000 mL than oxytocin. Misoprostol plus oxytocin combination evidence is less consistent and may relate to different routes and doses of misoprostol used in the studies. Carbetocin had the most favourable side-effect profile amongst the top three options; however, most carbetocin trials were small and at high risk of bias.Amongst the 11 ongoing studies listed in this review there are two key studies that will inform a future update of this review. The first is a WHO-led multi-centre study comparing the effectiveness of a room temperature stable carbetocin versus oxytocin (administered intramuscularly) for preventing PPH in women having a vaginal birth. The trial includes around 30,000 women from 10 countries. The other is a UK-based trial recruiting more than 6000 women to a three-arm trial comparing carbetocin, oxytocin and ergometrine plus oxytocin combination. Both trials are expected to report in 2018.Consultation with our consumer group demonstrated the need for more research into PPH outcomes identified as priorities for women and their families, such as women's views regarding the drugs used, clinical signs of excessive blood loss, neonatal unit admissions and breastfeeding at discharge. To date, trials have rarely investigated these outcomes. Consumers also considered the side-effects of uterotonic drugs to be important but these were often not reported. A forthcoming set of core outcomes relating to PPH will identify outcomes to prioritise in trial reporting and will inform futures updates of this review. We urge all trialists to consider measuring these outcomes for each drug in all future randomised trials. Lastly, future evidence synthesis research could compare the effects of different dosages and routes of administration for the most effective drugs.

Postpartum misoprostol for preventing maternal mortality and morbidity

BACKGROUND

The primary objective of postpartum haemorrhage (PPH) prevention and treatment is to reduce maternal deaths. Misoprostol has the major public health advantage over injectable medication that it can more easily be distributed at community level. Because misoprostol might have adverse effects unrelated to blood loss which might impact on mortality or severe morbidity, it is important to continue surveillance of all relevant evidence from randomised trials. This is particularly important as misoprostol is being introduced on a large scale for PPH prevention in low-income countries, and is commonly used for PPH treatment in well-resourced settings as well.

OBJECTIVES

To review maternal deaths and severe morbidity in all randomised trials of misoprostol for prevention or treatment of PPH.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (11 January 2013).

SELECTION CRITERIA

We included randomised trials including pregnant women who received misoprostol in the postpartum period, versus placebo/no treatment or other uterotonics for prevention or treatment of PPH, and reporting on maternal death, severe morbidity or pyrexia.We planned to include cluster- and quasi-randomised trials in the analysis, as a very large number of women will be needed to obtain robust estimates of maternal mortality but we did not identify any for this version of the review. In future updates of this review we will include trials reported only as abstracts if sufficient information is available from the abstract or from the authors.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and extracted data.

MAIN RESULTS

We included 78 studies (59,216 women) and excluded 34 studies.There was no statistically significant difference in maternal mortality for misoprostol compared with control groups overall (31 studies; 11/19,715 versus 4/20,076 deaths; risk ratio (RR) 2.08, 95% confidence interval (CI) 0.82 to 5.28); or for the trials of misoprostol versus placebo: 10 studies, 6/4626 versus 1/4707 ; RR 2.70; 95% CI 0.72 to 10.11; or for misoprostol versus other uterotonics: 21 studies, 5/15,089 versus 3/15,369 (19/100,000); RR 1.54; 95% CI 0.40 to 5.92. All 11 deaths in the misoprostol arms occurred in studies of misoprostol ≥ 600 µg.There was a statistically significant difference in the composite outcome 'maternal death or severe morbidity' for the comparison of misoprostol versus placebo (12 studies; average RR 1.70, 95% CI 1.02 to 2.81; Tau² = 0.00, I² = 0%) but not for the comparison of misoprostol versus other uterotonics (17 studies; average RR 1.50, 95% CI 0.50 to 4.52; Tau² = 1.81, I² = 69%). When we excluded hyperpyrexia from the composite outcome in exploratory analyses, there was no significant difference in either of these comparisons.Pyrexia > 38°C was increased with misoprostol compared with controls (56 studies, 2776/25,647 (10.8%) versus 614/26,800 (2.3%); average RR 3.97, 95% CI 3.13 to 5.04; Tau² = 0.47, I² = 80%). The effect was greater for trials using misoprostol 600 µg or more (27 studies; 2197/17,864 (12.3%) versus 422/18,161 (2.3%); average RR 4.64; 95% CI 3.33 to 6.46; Tau² = 0.51, I² = 86%) than for those using misoprostol 400 µg or less (31 studies; 525/6751 (7.8%) versus 185/7668 (2.4%); average RR 3.07; 95% CI 2.25 to 4.18; Tau² = 0.29, I² = 58%).

AUTHORS' CONCLUSIONS

Misoprostol does not appear to increase or reduce severe morbidity (excluding hyperpyrexia) when used to prevent or treat PPH. Misoprostol did not increase or decrease maternal mortality. However, misoprostol is associated with an increased risk of pyrexia, particularly in dosages of 600 µg or more. Given that misoprostol is used prophylactically in very large numbers of healthy women, the greatest emphasis should be placed on limiting adverse effects. In this context, the findings of this review support the use of the lowest effective dose. As for any new medication being used on a large scale, continued vigilance for adverse effects is essential and there is a need for large randomised trials to further elucidate both the relative effectiveness and the risks of various dosages of misoprostol.

Prostaglandins for preventing postpartum haemorrhage

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 METHODS

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.

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.

Misoprostol for the prevention and treatment of postpartum hemorrhage

INTRODUCTION

Uterotonic drugs are recommended for the prevention and treatment of postpartum hemorrhage (PPH), and oxytocin is considered the gold standard for both indications due to its established efficacy and safety. Unfortunately, access to oxytocin is still limited in many low-resource settings due to the need for cool storage, sterile equipment and administration by skilled personnel. Misoprostol , an E1 prostaglandin analog, has therefore been explored as an alternative for such settings due to its proven ability to induce uterine contractions, low cost, stability at room temperature and ease of administration.

AREAS COVERED

This review covers evidence from 51 randomized controlled trials for both prevention and treatment of PPH. It discusses efficacy and side effects in the context of the various doses that have been studied using oral, sublingual or rectal routes of administration for both indications.

EXPERT OPINION

There is now a solid body of evidence to justify the use of misoprostol for postpartum hemorrhage indications in many settings. The evidence supports use of 600 μg orally for the prevention of PPH and 800 μg sublingually for the treatment of PPH. There is no evidence to support the adjunct use of misoprostol following administration of conventional uterotonics for prevention or treatment purposes.

Misoprostol to prevent and treat postpartum haemorrhage: a systematic review and meta-analysis of maternal deaths and dose-related effects

OBJECTIVE

To review maternal deaths and the dose-related effects of misoprostol on blood loss and pyrexia in randomized trials of misoprostol use for the prevention or treatment of postpartum haemorrhage.

METHODS

We searched the Cochrane Controlled Trials Register and Pubmed, without language restrictions, for '(misoprostol AND postpartum) OR (misoprostol AND haemorrhage) OR (misoprostol AND hemorrhage)', and we evaluated reports identified through the Cochrane Pregnancy and Childbirth Group search strategy. Randomized trials comparing misoprostol with either placebo or another uterotonic to prevent or treat postpartum haemorrhage were checked for eligibility. Data were extracted, tabulated and analysed with Reviewer Manager (RevMan) 4.3 software.

FINDINGS

We included 46 trials with more than 40,000 participants in the final analysis. Of 11 deaths reported in 5 trials, 8 occurred in women receiving >or= 600 microg of misoprostol (Peto odds ratio, OR: 2.49; 95% confidence interval, CI: 0.76-8.13). Severe morbidity, defined as the need for major surgery, admission to intensive care, organ failure or body temperature >or= 40 degrees C, was relatively infrequent. In prevention trials, severe morbidity was experienced by 16 of 10,281 women on misoprostol and by 16 of 10,292 women on conventional uterotonics; in treatment trials, it was experienced by 1 of 32 women on misoprostol and by 1 of 32 women on conventional uterotonics. Misoprostol recipients experienced more adverse events than placebo recipients: 8 of 2070 versus 5 of 2032, respectively, in prevention trials, and 5 of 196 versus 2 of 202, respectively, in treatment trials. Meta-analysis of direct and adjusted indirect comparisons of the results of randomized trials showed no evidence that 600 microg are more effective than 400 microg for preventing blood loss > 1000 ml (relative risk, RR: 1.02; 95% CI: 0.71-1.48). Pyrexia was more than twice as common among women who received > 600 microg rather than 400 microg of misoprostol (RR: 2.53; 95% CI: 1.78-3.60).

CONCLUSION

Further research is needed to more accurately assess the potential beneficial and harmful effects of misoprostol and to determine the smallest dose that is effective and safe. In this review, 400 microg of misoprostol were found to be safer than > 600 microg and just as effective.

Prostaglandins for preventing postpartum haemorrhage

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

The Cochrane Pregnancy and Childbirth Group's Trials Register (February 2007) and PubMed (July 2006).

SELECTION CRITERIA

Randomized 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

Thirty-seven misoprostol and nine intramuscular prostaglandin trials (42,621 women) were included. Oral (seven trials, 2849 women) or sublingual misoprostol (relative risk (RR) 0.66; 95% confidence interval (CI) 0.45 to 0.98; one trial, 661 women) compared to placebo may be effective in reducing severe PPH and blood transfusion (RR 0.31; 95% CI 0.10 to 0.94; five oral misoprostol trials, 3519 women). The severe PPH analysis of oral misoprostol trials was not totalled due to significant heterogeneity. Compared to conventional injectable uterotonics, oral misoprostol was associated with higher risk of severe PPH (RR 1.32; 95% CI 1.16 to 1.51; 16 trials, 29,042 women) and use of additional uterotonics but with fewer blood transfusions (RR 0.81; 95% CI 0.64 to 1.02; 15 trials, 27,858 women). Additional uterotonic data were not totalled due to heterogeneity. Misoprostol use is associated with significant increases in shivering and a temperature of 38 degrees Celsius. There are scarce data comparing injectable prostaglandins with the conventional injectable uterotonics on severe PPH and the use of additional uterotonics, the primary outcomes of this review.

AUTHORS' CONCLUSIONS

Misoprostol orally or sublingually at a dose of 600 mcg shows promising results when compared to placebo in reducing blood loss after delivery. The margin of benefit may be affected by whether other components of 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.