Facts are important, especially when it comes to policies and discussions that impact patients. Claims regarding abortion “reversal” treatment are not based on science and do not meet clinical standards. The American College of Obstetricians and Gynecologists (ACOG) ranks its recommendations on the strength of the evidencei and does not support prescribing progesterone to stop a medication abortion.

Despite this, in states across the country, politicians are advancing legislation to require physicians to recite a script that a medication abortion can be “reversed” with doses of progesterone, to cause confusion and perpetuate stigma, and to steer women to this unproven medical approach. Unfounded legislative mandates like this one represent dangerous political interference and compromise patient care and safety.

What is Medication Abortion?

  • Medication abortion is the use of medications, rather than a procedure, to end a pregnancy. This safe and effective evidence-based regimen includes a combination of two drugs—mifepristone, taken first, and misoprostol, taken at a later point under counsel from a clinician.
  • Mifepristone stops the pregnancy growth by blocking the hormone progesterone; misoprostol makes the uterus contract to complete the abortion.
  • Medication abortion is more effective when both drugs are used, because mifepristone alone will not always cause abortion. In fact, as many as half of women who take only mifepristone continue their pregnancies.ii
  • Mifepristone and misoprostol are safe, effective medications that are also used for other indications.

So-called abortion “reversal” procedures are unproven and unethical.

  • A 2012 case series reported on six women who took mifepristone and were then administered varying progesterone doses. Four continued their pregnancies.iii This is not scientific evidence that progesterone resulted in the continuation of those pregnancies.
  • This study was not supervised by an institutional review board (IRB) or an ethical review committee, required to protect human research subjects, raising serious questions regarding the ethics and scientific validity of the results.
  • Case series with no control groups are among the weakest forms of medical evidence.iv
  • Subsequent case series used to support use of medication abortion reversal have had similar limitations, including no ethics approval, no control group, under-reporting of data, and no reported safety outcomes.
  • A 2020 study intending to evaluate medication abortion reversal in a controlled, IRB-approved setting was ended early due to safety concerns among the participants.v

Legislative mandates based on unproven, unethical research are dangerous to women’s health.

Politicians should never mandate treatments or require that physicians tell patients inaccurate information. This is an interference in the patient-clinical relationship and contradicts a fundamental principle of medical ethics.

Abortion is an essential part of comprehensive medical care, and a patient’s decision to end a pregnancy following appropriate consultation with their trusted medical professional should be treated with respect.

Additional ACOG Resources

ACOG Practice Bulletin 225 Medication Abortion Up to 70 Days of Gestation (October 2020)
ACOG Committee Opinion 815 Increasing Access to Abortion (December 2020)


  1. Hal C. Lawrence, M.D., “The American College of Obstetricians and Gynecologists Supports Access to Women’s Health Care,” Obstetrics & Gynecology vol. 125 1282, 1283 (Jun. 2015) available at
  2. Grossman D et al. “Continuing Pregnancy After Mifepristone and ‘Reversal’ of First-Trimester Medical Abortion: A Systematic Review,” Contraception 92 206–211 (Jun. 2015).
  3. Delgado G and Davenport M, “Progesterone Use to Reverse the Effects of Mifepristone,” The Annals of Pharmacotherapy vol. 46 (Dec. 2012).
  4. ACOG, Reading the Medical Literature
  5. Mitchell D. Creinin, M.D., “Mifepristone Antagonization With Progesterone to Prevent Medical Abortion,” Obstetrics & Gynecology vol. 135, 158-165 (Jan. 2020) available at