Source: Ibis Reproductive Health
The World Health Organization recommends two regimens for safe and effective medication abortion care throughout pregnancy: (1) misoprostol on its own, and (2) mifepristone in combination with misoprostol.1 These medications, when used correctly, successfully terminate 80-95% of pregnancies without the need for surgical intervention, depending on regimen and pregnancy duration.
Misoprostol alone is likely the most common method of medication abortion used worldwide—largely because, unlike mifepristone, misoprostol is widely available in many places over the counter without a prescription and at a low cost. The use of misoprostol in self-managed medication abortion—defined here as when a person takes pills on their own to end a pregnancy without clinical supervision—has risen globally, and is widely credited with declines in maternal morbidity and mortality.
Studies of self-managed use of misoprostol-alone regimens have found high levels of effectiveness, with 93-99% of participants reporting complete abortions without the need for surgical intervention.5-8 By comparison, a recent meta-analysis of all available clinical trial data on outcomes following clinically-managed use of misoprostol alone found that 78% of study participants across 13 clinical studies had a complete abortion without need for surgical intervention, though the studies varied widely in the misoprostol-only regimens used and time period under observation.
The differences observed in the effectiveness of misoprostol alone in self-managed contexts versus clinically-managed contexts are notable and should be viewed within the context of the study design and setting, specifically:
- Clinical studies typically evaluate abortion completion 1-2 weeks following the first dose, whereas studies of self-managed abortion typically assess completion at 3-4 weeks—thus abortions that were categorized as “incomplete” or “missed” in clinical studies might have resulted in a complete abortion with additional time.
- Clinical studies typically do not allow for additional doses of misoprostol within study protocol, whereas in self-managed settings, additional doses are often recommended as standard practice—thus abortions that were categorized as “incomplete” or “missed” in clinical studies might have resulted in a complete abortion with additional doses of misoprostol.
- Participants in studies conducted within the context of self-managed abortion may receive more detailed counseling on how to manage the medication abortion process, may be less interested in interacting with clinical settings, or may have less access to clinical care that could mean they are less inclined or able to seek early medical intervention than those in a clinical study setting where medical intervention may be more normalized and readily available.
Both regimens of medication abortion are safe and effective. The two regimens may result in different abortion experiences when it comes to duration of bleeding and side effects, but data from studies of self-managed medication abortion suggest that the safety and effectiveness of misoprostol-alone regimens is likely comparable to that of the combined regimen.5-8 In countries where abortion is legally restricted, mifepristone is often not registered for use and is largely unavailable both within and outside of the formal health care system. In the United States, for example, provision of mifepristone is restricted by the US Food and Drug Administration’s Risk Evaluation and Mitigation Strategy (REMS) guidance, which limits the number and type of providers who can prescribe mifepristone, and requires in-person clinic visits for provider-observed administration of this pill.
Misoprostol alone is a safe, effective, and acceptable regimen for abortion care that, with increased accessibility, has the potential to greatly expand access to medication abortion in a variety of contexts. More information on misoprostol alone as a method for abortion can be found here.
1. Medical Management of Abortion. Geneva: World Health Organization; 2018.
2. Ngo TD, Park MH, Shakur H, Free C. Comparative effectiveness, safety and acceptability of medical abortion at home and in a clinic: a systematic review. Bull World Health Organ. 2011;89(5):360-370.
3. Raymond EG, Harrison MS, Weaver MA. Efficacy of misoprostol alone for first-trimester medical abortion: A systematic review. Obstet Gynecol. 2019;133(1):137-147.
4. Briozzo L, Gómez Ponce de León R, Tomasso G, Faúndes A. Overall and abortion-related maternal mortality rates in Uruguay over the past 25 years and their association with policies and actions aimed at protecting women’s rights. Int J Gynaecol Obstet. 2016;134(1):004.
5. Foster AM, Arnott G, Hobstetter M. Community-based distribution of misoprostol for early abortion: Evaluation of a program along the Thailand Burma border. Contraception. 2017;96(4):242-247.
6. Stillman M, Owolabi O, Akinyemi A, et al. Women’s self-reported experiences using misoprostol obtained from drug sellers: A prospective cohort study in Lagos State, Nigeria. BMJ Open. 2020 (IN PRESS).
7. Moseson H, Jayaweera R, Raifman S, et al. Self-managed medication abortion outcomes: Results from a prospective pilot study. Reprod Health. 2020;17(1):164.
8. Moseson H, Jayaweera R, Egwuatu I, et al. Effectiveness of self-managed medication abortion with accompaniment support in Argentina and Nigeria: A prospective, observational cohort study and non-inferiority analysis with historical controls. Lancet Global Health. 2021; IN PRESS.