Mifepristone-Misoprostol Use for Second and Third Trimester Medical Termination of Pregnancy in a Canadian Tertiary Care Centre

Prior Cesarean Birth and Risk of Uterine Rupture in Second-Trimester Medication Abortions Using Mifepristone and Misoprostol: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the risk difference of uterine rupture when using current mifepristone and misoprostol regimens for second-trimester abortion among individuals with prior cesarean birth compared with those without prior cesarean birth.

DATA SOURCES

We searched the terms second trimester, induction, mifepristone, and abortion in PubMed, EMBASE, POPLINE, ClinicalTrials.gov , and Cochrane Library from inception until December 2022.

METHODS OF STUDY SELECTION

We included randomized trials and observational studies including a mixed cohort, with and without uterine scar, of individuals at 14-28 weeks of gestation who used mifepristone and misoprostol to end a pregnancy or to manage a fetal death. We excluded case reports, narrative reviews, and studies not published in English. Two reviewers independently screened studies.

TABULATION, INTEGRATION, AND RESULTS

Absolute risks with binomial CIs were calculated from pooled data. Using R software, we estimated total risk difference by the Mantel-Haenszel random-effects method without continuity correction. For studies with zero events, a continuity correction of 0.5 was applied for individual risk differences and plotted graphically with forest plots. Statistical heterogeneity was assessed with Higgins I2 statistics. Funnel plot assessed for publication bias. Of 198 articles identified, 22 met the inclusion criteria: seven randomized trials (n=923) and 15 observational studies (n=6,195). Uterine rupture risk with prior cesarean birth was 1.1% (10/874) (95% CI 0.6-2.1) and without prior cesarean birth was 0.01% (2/6,244) (95% CI 0.0-0.12). The risk difference was 1.23% (95% CI 0.46-2.00, I2 =0%). Of the 12 reported uterine ruptures, three resulted in hysterectomy.

CONCLUSION

Uterine rupture with mifepristone and misoprostol use during second-trimester induction abortion is rare, with the risk increased to 1% in individuals with prior cesarean birth.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42022302626.

Labour induction for termination of pregnancy with severe fetal anomalies after 24 weeks' gestation: a case series and systematic review of the literature

PURPOSE

Under some circumstances, individuals choose to undergo pregnancy termination for foetal anomalies in the second half of pregnancy. This report provides objective information on the clinical management of such cases and a systematic review of the literature on labour induction outcomes for third-trimester abortion using mifepristone-misoprostol.

MATERIALS AND METHODS

The study is a case series describing outcomes for labour induction abortion for foetal anomalies, at gestational age 24 weeks and beyond. A systematic review was performed, searching PubMed, Embase, and Cochrane databases. Two independent authors reviewed and quality assessed the data from the articles.

RESULTS

During a two-year period, 15 patients met inclusion criteria. Fourteen patients received mifepristone and misoprostol, and one received oxytocin. All delivered vaginally. Thirteen patients delivered within 24 hours of the first misoprostol dose, and half delivered within 12 hours. The average interval from misoprostol initiation to foetal expulsion was 15.5 hours in our series. The systematic review identified nine articles for inclusion, all retrospective studies. Labour induction protocols for mifepristone-misoprostol, reporting of gestational age, and key comparisons varied greatly.

CONCLUSIONS

The case series illustrates successful termination of pregnancy primarily using combined mifepristone-misoprostol. Certainty of current evidence is low, based on the GRADE framework. Future research is necessary on third-trimester outcomes with mifepristone-misoprostol.