Misoprostol plus mifepristone improves treatment success in early pregnancy loss

No baseline clinical factor is predictive of treatment success in women receiving medical management with misoprostol for early pregnancy loss, according to a study. However, the addition of mifepristone seems to improve treatment success.

“[T]hus, mifepristone treatment should be considered for management of early pregnancy loss regardless of baseline clinical factors,” the authors said.

A secondary analysis was conducted on a randomized trial comparing mifepristone–misoprostol with misoprostol alone for the management of early pregnancy loss. The following variables were included in the published prediction model for treatment success of single-dose misoprostol administered vaginally: active bleeding, type of early pregnancy loss (anembryonic pregnancy or embryonic and/or foetal demise), parity, gestational age, and treatment site. Previous significant predictors were vaginal bleeding within the past 24 hours and parity of 0 or 1 vs >1.

The authors performed bivariate analyses to determine if these characteristics predicted differential proportions of patients with treatment success or failure. Then, they carried out a logistic regression analysis to examine the effect of such predictors in each of the two treatment groups separately and in the full cohort as proxy for the combined treatment arm. Finally, the authors used receiver operating characteristic curves to test the ability of these predictors in association with misoprostol treatment success to discriminate between success and failure.

Of the 297 participants included in the primary study, 148 were randomized to the mifepristone–misoprostol combined treatment group and 149 in the misoprostol-alone treatment group. Among patients with vaginal bleeding at time of treatment, 15 of 17 (88 percent) in the combined treatment group and 12 of 17 (71 percent) in the monotherapy group experienced expulsion of pregnancy tissue. Among patients with a parity of 0 or 1, 94 of 108 (87 percent) in the combined treatment group and 66 of 95 (69 percent) in the monotherapy group had expulsion of pregnancy tissue.

These clinical characteristics did not predict treatment success in the combined cohort alone (area under the curve, 0.56, 05 percent confidence interval [CI], 0.48–0.64), and no other baseline clinical factors predicted treatment success in the misoprostol-alone treatment arm or mifepristone pretreatment arm, according to the authors.

In the full cohort, pretreatment with mifepristone (adjusted odds ratio [AOR], 2.51, 95 percent CI, 1.43–4.43) and smoking (AOR, 2.15, 95 percent CI, 1.03–4.49) significantly predicted treatment success.