The efficacy of misoprostol in reducing intraoperative blood loss in women undergoing elective cesarean section. A systematic review and meta-analysis

Abstract

Objectives: To evaluate the efficacy of misoprostol to minimized blood loss during and after cesarean delivery (CD).

Search strategy: Screening of MEDLINE, EMBASE, Web of Science, the Cochrane Central Register of Controlled Trials from inception to February 2021 using the keywords related to misoprostol, CD, postpartum hemorrhage, and intraoperative blood loss and their MeSH terms.

Selection criteria: Only RCTs were included. Participants included women undergoing CD whether elective or selective. Thirty studies including 6593 women, 26 in English, 2 in Thai, 1 in French, and 1 in Chinese.

Data collection and analysis: Data from all selected studies were extracted independently by two authors. Data extracted included location of the trial, sample size, inclusion and exclusion criteria, participants characteristics, intervention details including timing, dose, and route of drug administration. Outcomes assessed included estimated intraoperative and postoperative blood loss, occurrence of postpartum hemorrhage, the need for additional uterotonics, and hemoglobin difference.

Main results: Four studies (968 women) compared preoperative to postoperative misoprostol and found a mean difference in intraoperative blood loss of -205.00 (-339.22, -70.77), p = 0.003 and in postoperative blood loss -216.27 (-347.08, -85.46), p < 0.001 and a significantly lower need for additional uterotonics with a risk ratio of 0.54 (0.46, 0.64), p < 0.00001. Twenty-two studies (4701 participants) compared misoprostol to oxytocin. There was a mean difference in intraoperative blood loss of -108.43 (-156.04, -60.82), p < 0.0001. Nine of these trials with 1978 participants evaluated postoperative blood loss. These found a mean difference of -64.12 (-116.19, -12.04) with a p = 0.02. Fourteen trials with 3166 participants measured the difference between preoperative and postoperative hemoglobin. These found a mean difference of -0.25 (-0.35, -0.15) with a p < 0.001. Twenty trials with 4416 participants measured the need for administration of additional uterotonics. These found a risk ratio of 0.62 (0.49, 0.78) with a p value of <0.001.

Conclusion: The combined use of misoprostol and oxytocin during CD is effective in reducing blood loss during and after CD.

Keywords: cesarean delivery; intraoperative blood loss; misoprostol; postoperative blood loss.