Factors affecting the outcome of early medical abortion: a review of 4132 consecutive cases

Abstract

Objective To assess the outcome of a regimen of a reduced dose of mifepristone followed by one or two doses of vaginal misoprostol as a non-surgical method for termination of pregnancy.Design Prospective observational study.Setting Aberdeen Royal Infirmary, Aberdeen, Scotland.Population Women seeking abortion under the 1967 Abortion Act.Methods Factors influencing the outcome in a consecutive series of 4132 women undergoing early medical abortion in one Scottish teaching hospital since 1994.Main outcome measures Complete abortion rates following one or two doses of misoprostol. The effect of age, gestation, previous pregnancy and previous termination on complete abortion rates following the medical regimen.Results Of the 4132 women, 95 (2.3%) aborted within 48 hours of mifepristone and a further 3942 (95.4%) achieved complete abortion following administration of one or two doses of misoprostol. Thus, the overall complete abortion rate was 97.7% (4037/4131). A total of 94 (2.3%) women required surgical intervention of whom 13 (0.3%) had a continuing pregnancy. Following change of the regimen to include the possibility of two doses of misoprostol the continuing pregnancy rates were significantly reduced (OR ¼ 5.88) and gestation ceased to have an effect on overall efficacy. Women who had a previous abortion were more likely to have a failed medical abortion (OR ¼ 2.09), while women with no previous termination, but a previous live birth were more likely to have a failed abortion (OR ¼ 2.03).Conclusion Mifepristone in combination with one to two doses of vaginal misoprostol is an effective regimen for early medical abortion. The option of administering two doses of misoprostol significantly reduced the ongoing pregnancy rates and abolished the effect of gestation on overall efficacy. Previous termination was the strongest predictor of failed medical abortion.

Comparison of unscheduled re-attendance and contraception at discharge, among women having the final stage of early medical abortion at home and those remaining in hospital

“…Although it has previously been shown in a large observational study of over 4000 cases of early medical abortion that addition of a further dose of misoprostol can reduce the ongoing pregnancy rate, we did not find a significant difference in the number of ongoing pregnancies following EMD treatment or day case treatment 14. While we do not know what proportion of women in the day case group received the extra dose of misoprostol, clearly it is reassuring that women in our study who chose EMD (and thus received a single dose of misoprostol only) were not disadvantaged by this.…”

Initiating intramuscular depot medroxyprogesterone acetate 24–48 hours after mifepristone administration does not affect success of early medical abortion

“…In concordance with previous research, we have shown that both previous termination and increasing gestation are factors associated with failure of EMA 16 17. Previous studies have reported that EMA failure rate and subsequent requirement for surgical intervention was higher in women who were parous compared with those who were nulliparous 16. In the present study, we have not shown any significant association between parity and success of EMA.…”

Home self-administration of misoprostol for medical abortion up to 56 days' gestation

“…12,17 These findings may be useful in counselling women undergoing medical abortion in home settings. However, analgesia requirements will need to be evaluated in different settings and preferably in the context of a randomised trial.…”

“…[10][11][12][13][14][15][16] Caution, nonetheless, is essential in advising women about undergoing medical abortion at home. Ensuring that women live within a reasonable distance of the hospital remains important at this stage until more safety data become available.…”

“…Ashok et al 12 reported the outcomes of 4132 women undergoing medical abortion up to 63 days' gestation and reported a complete abortion rate of 97.7%. However, 0.3% of women had a continuing pregnancy.…”