The Truth About ‘Abortion Pill Reversal’

What is ‘abortion pill reversal’?

Anti-abortion organizations claim that medication abortion can possibly be “reversed” by administering progesterone orally, vaginally, or through an injection to a pregnant person who has initiated a medication abortion.[1] Medication abortion involves two medicines: mifepristone which ends a pregnancy by blocking progesterone, and misoprostol which causes cramping and bleeding to empty the uterus.[2] In an “abortion pill reversal” or “abortion reversal”, progesterone is given after the first medication, mifepristone, and prior to the second medication, misoprostol.

This potentially dangerous practice is increasingly being promoted by Unregulated Pregnancy Centers (UPCs, also known as Crisis Pregnancy Centers or anti-abortion centers), including several in Montana. However, there are no reputable national or international clinical guidelines that recommend the use of progesterone to reverse the effect of mifepristone. There is also no scientific evidence that progesterone administered after mifepristone increases the likelihood of continued pregnancy.[3]

PROMOTING SO-CALLED ‘ABORTION REVERSAL’ PUTS PREGNANT PEOPLE AT RISK. MONTANANS DESERVE EVIDENCE-BASED AND PATIENT-CENTERED CARE FROM LICENSED HEALTHCARE PROVIDERS.

Medication abortion is proven to be safe and effective

Medication abortion using a combined regimen of mifepristone and misoprostol is safe, effective, and increasingly the most common method to end a pregnancy.[4] Medication abortion is more effective when both drugs are used because mifepristone alone will not always cause abortion. Pregnant individuals who take only mifepristone (and who forgo taking misoprostol) may continue being pregnant.[5] And, if mifepristone ends the pregnancy and misoprostol is not taken as recommended (as is the practice with ‘abortion pill reversal’), a person may experience excessive bleeding or other complications necessitating further medical care. Without proper medical care these complications can be life threatening.[6]

‘Abortion reversal’ is not supported by science

The concept of abortion reversal gained traction following a 2012 case series where six women who took mifepristone were then administered varying progesterone doses. Four continued their pregnancies. This study had no control group and there is no conclusive evidence that the four pregnancies that continued would not have continued without progesterone. Further, the study was not supervised by an institutional review board (IRB) or an ethical review committee, nor has it been replicated.[7]

A 2020 study intending to evaluate medication abortion reversal in a controlled IRB-approved setting was ended early due to safety concerns and high rates of complications among participants. Only 12 participants enrolled before the study was discontinued and no conclusions could be drawn regarding the efficacy of progesterone to counteract mifepristone in pregnancy. Given the multiple occurrences of severe hemorrhage, the study concludes patients in early pregnancy who use only mifepristone may be at high risk of significant hemorrhage.[6] Research on the safety and efficacy of abortion reversal remains limited, given known safety concerns and the extremely low rates of regret following an abortion.

‘Abortion reversal’ in Montana

Misguided laws promoting abortion reversal have been on the rise in recent years. In 2021, Montana lawmakers passed HB171: The Montana Abortion-Inducing Drug Risk Protocol Act. This bill included numerous restrictions on medication abortion and required abortion providers to inform patients about abortion reversal.[8] The law was immediately challenged and eventually struck down by a Montana district court judge in 2024.[9] Although states such as Colorado have passed laws banning abortion reversal, no such restrictions currently exist in Montana. At least three unregulated pregnancy centers located in Billings, Miles City, and Sidney, currently promote abortion reversal on their websites.[10, 11, 12]

People are confident in their decisions to have an abortion

The overwhelming majority of people requesting an abortion are clear about their decision, and want treatment as soon as possible. Research has shown that 97.5% of individuals believe that their decision to have an abortion was the right choice, roughly one week after their abortion.[13] Five years after an abortion, almost all people (99%) said it was the right decision.[14] A systematic review showed only 0.004% of patients who took mifepristone between 2000 and 2012 ended up deciding to continue their pregnancies.[5]

Pregnant people deserve respectful, evidence-based guidance and care

Abortion is an essential part of comprehensive medical care. A person’s decision to end a pregnancy should be treated with respect. In the rare case a person changes their mind during a medication abortion, they should be offered nondirective, unbiased counselling regarding their options, and the benefits and risks of each option. If they wish to continue their pregnancy they should be monitored expectantly and offered additional medical care as indicated. “Counseling” or “education” promoting ‘abortion reversal’ causes confusion and perpetuates abortion stigma. Individuals who prescribe ‘abortion reversal’ at UPCs are acting outside regulated healthcare systems and are unlikely to have medical credentials to provide licensed patient care.[3, 13]

[1] Abortion pill reversal. (n.d.). FAQs. https://www.abortionpillreversal. com/abortion-pill-reversal/faq [2] Where can I get an abortion? | U.S. Abortion Clinic Locator. (n.d.). https://www.abortionfinder.org/abortion-types/pill [3] Medication abortion reversal is not supported by science. (n.d.). https://www.acog.org/advocacy/facts-are-important/medicationabortion-reversal-is-not-supported-by-science [4] The Availability and Use of medication Abortion | KFF. (2025, March 10). KFF. https://www.kff.org/womens-health-policy/fact-sheet/theavailability-and-use-of-medication-abortion/ [5] Grossman, D., White, K., Harris, L., Reeves, M., Blumenthal, P. D., Winikoff, B., & Grimes, D. A. (2015). Continuing pregnancy after mifepristone and “reversal” of first-trimester medical abortion: a systematic review. Contraception, 92(3), 206–211. https://doi. org/10.1016/j.contraception.2015.06.001 [6] Creinin, M. D., Hou, M. Y., Dalton, L., Steward, R., & Chen, M. J. (2019). Mifepristone antagonization with progesterone to prevent medical abortion. Obstetrics and Gynecology, 135(1), 158–165. https://doi. org/10.1097/aog.0000000000003620 [7] Delgado, G., & Davenport, M. L. (2012). Progesterone use to reverse the effects of mifepristone. Annals of Pharmacotherapy, 46(12), 1723. https://doi.org/10.1345/aph.1r252 [8] Montana Legislature. (n.d.). 67th Legislature HB 171. In Montana Abortion-Inducing Drug Risk Protocol Act. https://archive.legmt.gov/ bills/2021/billpdf/HB0171.pdf [9] Silvers, M. (2024, February 29). Abortion restrictions struck down by state court. Montana Free Press. https://montanafreepress. org/2024/02/29/montana-abortion-restrictions-struck-down-by-statecourt/ [10] Services and Support for Early Pregnancies. (2024, October 31). Abortion pill reversal. LaVie. https://laviebillings.org/abortion-pillreversal/ [11] Services. (n.d.). https://outreachclinicmc.org/services/ [12] Sunrise Pregnancy Support Center - Sidney, MT - Abortion information. (n.d.). https://www.sunrisepregnancy.org/be-informed/ abortion-information [13] The Royal College of Obstetricians and Gynaecologists (RCOG), The Faculty of Sexual and Reproductive Healthcare (FSRH), The Royal College of Midwives (RCM), & The British Society of Abortion Care Providers (BSACP). (n.d.). Joint statement on ‘Abortion reversal.’ https:// www.rcog.org.uk/media/nbahkgvo/rcog-fsrh-abortion-reversalposition-statement.pdf [14] Rocca, C. H., Samari, G., Foster, D. G., Gould, H., & Kimport, K. (2020). Emotions and decision rightness over five years following an abortion: An examination of decision difficulty and abortion stigma. Social Science & Medicine, 248, 112704. https://doi.org/10.1016/j. socscimed.2019.112704