One-day versus two-day mifepristone-misoprostol interval prior to initiation of misoprostol during late second trimester medication abortion: A cohort study

Objectives: To compare one-day versus two-day mifepristone-misoprostol interval in late second trimester medication abortion.

Study design: This retrospective cohort study was conducted at St. Paul's Hospital Millennium Medical College, in Ethiopia. Data were collected retrospectively and analysed with SPSS 23 using simple descriptive analysis, t-test, Chi-squared test, and regression analysis, as appropriate. P-value < 0.05 and adjusted odds ratio (AOR) with 95% CI were used to present results significance.

Results: A total of 282 women who had medication abortion in the late second trimester (167 with one-day and 115 with two-day mifepristone-misoprostol intervals) at 20-28 weeks of gestation were analysed. Both median and mean induction to expulsion interval (I-E) were much higher in the one-day mifepristone-misoprostol (mife-miso) interval than in the two-day mife-miso interval group. The median (and mean) I-E in the one-day interval group was 24 hours (21.9+/-6.6 hours) compared to 12 hours (14.6+/-8.8 hours) in the two-day mife-miso interval group (p-value < 0.001). Expulsion rate within 12 hours of starting misoprostol was significantly higher in the two-day cohort than in the one-day cohort (73% vs 25.6%, p-value < 0.001, aOR = 19.08 95%, CI = 5.1-70.7).

Conclusions: For second trimester medication abortion at later gestation, a two-day mifepristone-to-misoprostol interval significantly reduces induction to expulsion time compared to a one-day interval.

Implications: Compared to one-day interval, administration of mifepristone two days prior to misoprostol initiation has a shorter interval of induction to expulsion and a higher rate of abortion completion within 12 hours of initiation of misoprostol during late second trimester medication abortion.