Mifepristone-misoprostol combo shortens time to delivery during late pregnancy loss

Administration of mifepristone, followed by misoprostol,  shortened induction-to-delivery intervals in women who lost their babies during the third trimester of pregnancy compared with misoprostol alone, results of a systematic review has shown.

The median time from induction to delivery was 10.2 hours after administration of mifepristone and misoprostol, which was significantly lower than the 16.9 hours induction time after administration of misoprostol alone. [ACOG 2021, abstract 1652097]

“Although there was heterogeneity among the nine studies we included, a meta-analysis of five similar trials did find a statistically significant decrease in the time from induction of labour to delivery with the combination therapy,” said study investigator Dr Kaitlyn Mayer from Virginia Commonwealth University Medical Center in Richmond, Virginia, US, who presented the results at the ACOG 2021 virtual meeting.

Mayer and team reviewed three retrospective cohorts, two prospective cohorts, and four randomized trials that included 695 women who had a mean gestational age of 32.6 weeks.

24 hours a critical period

Many of the women were able to deliver in 24 hours. This is critical as shortening the duration of medical management for third-trimester loss may help to reduce trauma in these women, she highlighted.

“For any woman who is diagnosed with a foetal demise, or a stillbirth, tenets of care include safety and efficacy, but also being respectful of the patient experience,” Mayer added. “Anything that we can do to increase the safety and efficacy of an induction for these patients, but with due respect for their experience, is really important.”

Mifepristone is an antiprogesterone that has been shown to significantly increase the efficacy and safety of prostaglandins such as misoprostol in the management of first-trimester loss and abortion care. [N Engl J Med 2018;378:2161-2170]

Generally, the management of intrauterine foetal demise has been extrapolated from trials of second-trimester induced abortion because of a paucity of quality studies that have investigated the use of this regimen in the third-trimester pregnancy loss setting, said Mayer.

As mifepristone is regulated under the US Food and Drug Administration risk evaluation and mitigation strategies (REMS) protocol, Mayer hopes that more data about its benefits will support greater access to the drug, including its deregulation.

Use combo therapy whenever feasible

“Providers caring for patients who choose to manage late pregnancy loss with induction of labour should utilize combination therapy with mifepristone and misoprostol compared with misoprostol alone whenever possible,” Mayer said.

In addition, future studies are warranted to determine the optimal dosing of misoprostol when used with mifepristone in the medical management of third-trimester pregnancy loss.