Comparing and combining evidence of treatment effects in randomized and nonrandomized studies on the use of misoprostol to prevent postpartum hemorrhage

OBJECTIVE

Postpartum hemorrhage (PPH) is a preventable condition and the main cause of maternal death worldwide. Evidence on the effectiveness of misoprostol in the prevention of PPH has been generated from both randomized controlled trials (RCTs) and nonrandomized studies (NRS). This study aimed to compare the results of RCTs and NRS, and to compare Classical and Bayesian approaches of combining the results of RCTs and NRS on the use of misoprostol versus placebo in the prevention of PPH.

METHODS

We searched MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials for appropriate studies. We pooled estimates of effects from RCTs and NRS seperately, using random-effects models, then merged them using classical and Bayesian random effects meta-analysis.

RESULTS

A total of 34 studies (20 RCTs and 14 NRS) involving 74 204 participants were identified. The summary odds ratio (OR) from RCTs for the use of misoprostol in the prevention of PPH was 0.69 (95% confidence interval [CI]: 0.59 to 0.80). The summary OR from NRS was 0.46 (95% CI: 0.36 to 0.63). Classical and Bayesian approaches of combining the two study designs both showed benefit of misoprostol in preventing PPH, with similar effects.

CONCLUSIONS

Both RCTs and NRS show comparable significant benefit for the use of misoprostol in the prevention of PPH.

How to improve the quality of care for women with postpartum haemorrhage at Onandjokwe Hospital, Namibia: quality improvement study

Background

Postpartum haemorrhage (PPH) is the leading direct cause of maternal morbidity and mortality worldwide. The sustainable development goals aim to reduce the maternal mortality ratio to 70 per 100,000 live births. In Namibia, the ratio was reported as 265 per 100,000 live births in 2015 and yet little is published on emergency obstetric care. The majority of deliveries in Namibia are facility-based. The aim of this study was to assess and improve the quality of care for women with PPH at Onandjokwe Hospital, Namibia.

Methods

A criterion-based audit cycle in all 82 women with PPH from 2015 using target standards for structure, process and outcomes of care. The audit team then planned and implemented interventions to improve the quality of care over a 10-month period. The audit team repeated the audit on all 70 women with PPH from the same 10-month period. The researchers compared audit results in terms of the number of target standards achieved and any significant change in the proportion of patients’ care meeting the predetermined criteria.

Results

In the baseline audit 12/19 structural, 0/9 process and 0/3 outcome target standards were achieved. On follow up 19/19 structural, 6/9 process and 2/3 outcome target standards were met. There was one maternal death in the baseline group and none in the follow up group. Overall 6/9 process and 2/3 outcome criteria significantly improved (p <  0.05) from baseline to follow up. Key interventions included training of nursing and medical staff in obstetric emergencies, ensuring that guidelines and standard operating protocols were easily available, reorganising care to ensure adequate monitoring of women postpartum and ensuring that essential equipment was available and functioning.

Conclusion

The study demonstrates that the quality of care for emergency obstetrics can be improved by audit cycles that focus on the structure and process of care. Other hospitals in Namibia and the region could adopt the process of continuous quality improvement and similar strategies.

Prophylactic management of postpartum haemorrhage in the third stage of labour: an overview of systematic reviews

BACKGROUND

Postpartum haemorrhage is a direct cause of maternal death worldwide and usually occurs during the third stage of labour. Most women receive some type of prophylactic management, which may include pharmacological or non-pharmacological interventions. The objective of this study was to summarize systematic reviews that assessed the effects of postpartum haemorrhage prophylactic management during the third stage of labour.

METHODS

We applied the guidelines for conducting an overview of reviews from the Cochrane Handbook for Systematic Reviews of Interventions. We searched MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews to identify all relevant systematic reviews of randomized controlled trials of prophylactic management of postpartum haemorrhage in the third stage of labour compared with no treatment, placebo, or another management technique. Two review authors independently extracted data and assessed methodological quality using a measurement tool to assess reviews and quality of evidence using the Grades of Recommendation, Assessment, Development, and Evaluation for primary outcomes, summarizing results narratively.

RESULTS

We identified 29 systematic reviews: 18 Cochrane and 11 non-Cochrane. Cochrane systematic reviews were high quality, while the quality of non-Cochrane systematic reviews varied. The following techniques suggested effective, third-stage interventions to reduce the incidence of severe postpartum haemorrhage: active management of the third stage of labour compared to physiological management, active management compared to expectant management, administration of oxytocin compared to placebo, and use of tranexamic acid compared to placebo. The following third-stage management approaches reduced the need for blood transfusion: active management compared to physiological management, active management compared to expectant management, oral misoprostol compared to placebo, and tranexamic acid compared to placebo.

CONCLUSIONS

No effective prophylactic management techniques were identified for maternal mortality. Most methods of effective prophylactic management of postpartum haemorrhage were supported by evidence; however, they were limited to low- or moderate-quality evidence, and high-quality studies are therefore needed. Outcome measures of the included systematic reviews varied. It is recommended that outcome measures in preventive postpartum haemorrhage intervention trials align with the World Health Organization guidelines.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO: CRD42016049220 .

Modeling maternal mortality in Bangladesh: the role of misoprostol in postpartum hemorrhage prevention

BACKGROUND

Bangladesh is one of the few countries that may actually achieve the fifth Millennium Development Goal (MDG) in time, despite skilled birth attendance remaining low. The purpose of this paper is to examine the potential role misoprostol can play in the decline of maternal deaths attributed to postpartum hemorrhage (PPH) in Bangladesh.

METHODS

Using data from a misoprostol and blood loss measurement tool feasibility study in Bangladesh, observed cause specific maternal mortality ratios (MMRs) were estimated and contrasted with expected ratios using estimates from the Bangladesh Maternal Mortality Survey (BMMS) data. Using Crystal Ball 7 we employ Monte Carlo simulation techniques to estimate maternal deaths in four scenarios, each with different levels of misoprostol coverage. These scenarios include project level misoprostol coverage (69%), no (0%), low (40%), and high (80%) misoprostol coverage. Data on receipt of clean delivery kit, use of misoprostol, experience of PPH, and cause of death were used in model assumptions.

RESULTS

Using project level misoprostol coverage (69%), the mean number of PPH deaths expected was 40 (standard deviation = 8.01) per 100,000 live births. Assuming no misoprostol coverage (0%), the mean number of PPH deaths expected was 51 (standard deviation = 9.30) per 100,000 live births. For low misoprostol coverage (40%), the mean number of PPH deaths expected was 45 (standard deviation = 8.26) per 100,000 live births, and for high misoprostol coverage (80%), the mean number of PPH deaths expected was 38 (standard deviation = 7.04) per 100,000 live births.

CONCLUSION

This theoretical exercise hypothesizes that prophylactic use of misoprostol at home births may contribute to a reduction in the risk of death due to PPH, in addition to reducing the incidence of PPH. If findings from this modeling exercise are accurate and uterotonics can prevent maternal death, misoprostol could be the tool countries need to further reduce maternal mortality at home births.

Prevention of postpartum hemorrhage in low-resource settings: current perspectives

BACKGROUND

Postpartum hemorrhage (PPH) is the leading cause of maternal death in low-income countries and is the primary cause of approximately one-quarter of global maternal deaths. The purpose of this paper is to provide a review of PPH prevention interventions, with a particular focus on misoprostol, and the challenges and opportunities that preventing PPH in low-resource settings presents.

METHODS

Using PubMed, we conducted a review of the literature on the randomized controlled trials of interventions to prevent PPH. We then searched PubMed and Google Scholar for nonrandomized field trials of interventions to prevent PPH. We limited our review to interventions that are discussed in the current World Health Organization (WHO) recommendations for PPH prevention and present evidence regarding the use of these interventions. We focused our review on nondrug PPH prevention interventions compared with no intervention and uterotonics versus placebo; this review does not decipher the relative effectiveness of uterotonic drugs. We describe challenges to and opportunities for scaling up PPH prevention interventions.

RESULTS

Active management of the third stage of labor is considered the "gold standard" strategy for reducing the incidence of PPH. It combines nondrug interventions (controlled cord traction and cord clamping) with the administration of an uterotonic drug, the preferred uterotonic being oxytocin. Unfortunately, oxytocin has limited application in resource-poor countries, due to its heat instability and required administration by a skilled provider. New heat-stable drugs and drug formulations are currently in development that may improve the prevention of PPH; however, misoprostol is a viable option for provision at home by a lay health care worker or the woman herself, in the interim.

CONCLUSION

As the main cause of maternal mortality worldwide, PPH prevention interventions need to be prioritized. Increased access to prophylactic uterotonics, regardless of where deliveries occur, should be the primary means of reducing the burden of this complication.