The effect of carbetocin compared to misoprostol in management of the third stage of labor and prevention of postpartum hemorrhage: a systematic review

BACKGROUND

Postpartum hemorrhage (PPH) and the amount of blood loss are directly related to management of the third stage of labor. No previous report has compared the effects of carbetocin to those of misoprostol. The aim of this systematic review was to compare the effects of carbetocin to those of misoprostol for management of the third stage of labor and for the prevention of PPH.

METHODS

We searched the Cochrane Library (Central), Web of Science, Scopus, Science Direct, Ovid, clinicaltrial.gov , and PubMed databases on December 28, 2017. Data extraction and risk of bias assessment were performed by 2 of the authors independently. Individual and pooled incidences were calculated for the included studies, with 95% confidence intervals (CIs). We used a fixed model for forest plots without heterogeneity and a random effect model for those with heterogeneity.

RESULTS

Our search identified 117 studies; however, 29 studies were duplicate. Of the 88 non-duplicate studies, 5 met the inclusion criteria. Of these five studies, two are currently underway. Hence, three studies were finally included in our meta-analysis. The pooled estimate of the impact of carbetocin on PPH (500-1000 ml) was (OR 0.27, 95% CI 0.14-0.50). Carbetocin significantly reduced the need for additional uterotonics (RR 0.28, 95% CI 0.15 to 0.49). Reduction in the hemoglobin level and blood loss during the third stage of labor was significantly lower in women who received carbetocin than in those who received misoprostol. The length of the third stage of labor was significantly lower in women who received carbetocin than in those who received misoprostol. The incidence of side effects, such as heat sensation, metallic taste, fever, and shivering, were significantly lower in women who received carbetocin than in those who received misoprostol.

CONCLUSION

Although this review showed that carbetocin is effective for decreasing PPH, blood loss, the length of the third stage of labor, and the need for additional uterotonics, this conclusion should be considered with caution. Because assessment of PPH is a subjective issue and it is uncertain whether outcomes were assessed blindly in respect to treatment. We recommend future research to verify our findings. Also clinicians may like to consider use of carbetocin for women with low risk for PPH.

Treatment for primary postpartum haemorrhage

BACKGROUND

Primary postpartum haemorrhage (PPH) is one of the top five causes of maternal mortality in both developed and developing countries.

OBJECTIVES

To assess the effectiveness and safety of any intervention used for the treatment of primary PPH.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2013).

SELECTION CRITERIA

Randomised controlled trials comparing any interventions for the treatment of primary PPH.

DATA COLLECTION AND ANALYSIS

We assessed studies for eligibility and quality and extracted data independently. We contacted authors of the included studies to request more information.

MAIN RESULTS

Ten randomised clinical trials (RCTs) with a total of 4052 participants fulfilled our inclusion criteria and were included in this review.Four RCTs (1881 participants) compared misoprostol with placebo given in addition to conventional uterotonics. Adjunctive use of misoprostol (in the dose of 600 to 1000 mcg) with simultaneous administration of additional uterotonics did not provide additional benefit for our primary outcomes including maternal mortality (risk ratio (RR) 6.16, 95% confidence interval (CI) 0.75 to 50.85), serious maternal morbidity (RR 0.34, 95% CI 0.01 to 8.31), admission to intensive care (RR 0.79, 95% CI 0.30 to 2.11) or hysterectomy (RR 0.93, 95% CI 0.16 to 5.41).  Two RCTs (1787 participants) compared 800 mcg sublingual misoprostol versus oxytocin infusion as primary PPH treatment; one trial included women who had received prophylactic uterotonics, and the other did not. Primary outcomes did not differ between the two groups, although women given sublingual misoprostol were more likely to have additional blood loss of at least 1000 mL (RR 2.65, 95% CI 1.04 to 6.75). Misoprostol was associated with a significant increase in vomiting and shivering.Two trials attempted to test the effectiveness of estrogen and tranexamic acid, respectively, but were too small for any meaningful comparisons of pre-specified outcomes.One study compared lower segment compression but was too small to assess impact on primary outcomes.We did not identify any trials evaluating surgical techniques or radiological interventions for women with primary PPH unresponsive to uterotonics and/or haemostatics.

AUTHORS' CONCLUSIONS

Clinical trials included in the current review were not adequately powered to assess impact on the primary outcome measures. Compared with misoprostol, oxytocin infusion is more effective and causes fewer side effects when used as first-line therapy for the treatment of primary PPH. When used after prophylactic uterotonics, misoprostol and oxytocin infusion worked similarly. The review suggests that among women who received oxytocin for the treatment of primary PPH, adjunctive use of misoprostol confers no added benefit.The role of tranexamic acid and compression methods requires further evaluation. Furthermore, future studies should focus on the best way to treat women who fail to respond to uterotonic therapy.