Can you 'reverse' a medication abortion? Here's what experts say.

Medication abortion pills with reverse symbol on red background.
Experts say a "reversal" treatment for medication abortion isn't supported by science. (Illustration: Nathalie Cruz; photo: Getty Images)

California attorney general Rob Bonta filed a lawsuit against the national anti-abortion group Heartbeat International and RealOptions Obria, which are crisis pregnancy centers located in Northern California, for allegedly making fraudulent and misleading claims about abortion pill reversal treatments, according to a statement released on Sept. 21.

"HBI and RealOptions took advantage of pregnant patients at a deeply vulnerable time in their lives, using false and misleading claims to lure them in and mislead them about a potentially risky procedure," he states. "We are launching today’s lawsuit to put a stop to their predatory and unlawful behavior." He added: "There is absolutely no scientific basis to support such a claim" that abortion pill reversals actually work.

Bonta isn't the first government official to call out this practice. In April, Kansas Gov. Laura Kelly vetoed legislation that would require clinics to tell patients that a medication abortion can be "reversed" using an unproven treatment.

"Kansans made clear that they believe personal health care decisions should be made between a woman and her doctor, not politicians in Topeka," Kelly said in a statement after rejecting the legislation. She also noted that there was "uncertain science" behind the concept of an abortion reversal.

Kelly has pushed back against this kind of legislation before: She also vetoed a similar measure on abortion reversal in 2019.

Medication abortion accounts for more than half of all abortions performed in the U.S. It involves taking two prescription medications: mifepristone, followed by misoprostol. Mifepristone "blocks the hormone progesterone, which supports a healthy pregnancy, and misoprostol causes uterine cramping and shedding of the endometrium," women's health expert Jennifer Wider tells Yahoo Life.

A "reversal" involves giving doses of progesterone after mifepristone is taken — but before misoprostol is taken — to try to prevent pregnancy loss. (Supplemental progesterone is used to try to lower the risk of miscarriage in certain pregnancies, Dr. Lauren Streicher, a clinical professor of obstetrics and gynecology at Northwestern University Feinberg School of Medicine, tells Yahoo Life.)

But this reversal treatment isn't supported by science. "There is no medical evidence to support the assertion that a medication abortion can be reversed," Sarah Diemert, director of medical standards integration and evaluation at Planned Parenthood Federation of America, tells Yahoo Life. In fact, the American College of Obstetricians and Gynecologists (ACOG) directly spoke out about this online, adding that "legislative mandates based on unproven, unethical research are dangerous to women's health."

But where did this concept come from and what purpose does it serve? Here's the deal.

The abortion reversal concept comes from a small and flawed study

The idea of an abortion reversal comes from a 2012 case series on six women who took mifepristone and were then given different doses of progesterone. Four of those women continued with their pregnancies, but ACOG points out that it's difficult to know if the progesterone caused the pregnancies to continue or if other factors were at play. The study also did not have a control group (i.e., patients who did not take progesterone after mifepristone) and is therefore considered weak evidence, ACOG says.

Taking mifepristone alone also isn't a guarantee that an abortion will work, Streicher says: "The reason you use mifepristone and misoprostol is that if you use mifepristone alone, it doesn't always work."

The study wasn't supervised by an institutional review board or an ethical review committee, which ACOG says also raises a lot of questions about ethics. "This was a small experiment and its mixed outcomes is not science," Wider says. "The so-called reversing of abortion is not accepted as a safe or ethical procedure in modern medicine."

There was also a 2020 study that sought to evaluate abortion reversal in a controlled setting, but ACOG says it was ended early due to safety concerns in participants.

So, why do claims that abortion can be reversed exist?

The idea of telling people that they can reverse an abortion seems like it would make people who are uncertain if they want to terminate a pregnancy feel more comfortable at least starting the process. So why do some anti-abortion advocates want patients to be told that an abortion can be reversed?

It's not entirely clear. "It's completely political — and throws facts and medical evidence out the window for political gain," Wider says. Streicher says she has "no clue" why someone would want to promote an abortion reversal, but theorizes that this might be a reason: "Maybe they think that if we can get to them soon enough and make them realize what a big mistake they've made, we can reverse it."

Overall, the concept of an abortion reversal exists "to create confusion, stigma and unnecessary restrictions around abortion, which has been overwhelmingly proven to be safe and effective," Diemert says.

Wider says the growing movement of politicians telling doctors how they can and should practice medicine is "horrible." She adds, "The welfare of the patients is never the top priority, which it always should be."

Wellness, parenting, body image and more: Get to know the who behind the hoo with Yahoo Life's newsletter. Sign up here.