Conservative lawmakers are pushing for measures that require clinics to inform women about their option of being able to stop or “reverse” the abortions.

The ability to “reverse” abortions using unproven protocol was a sensational claim made by San Diego physician George Delgado, who opposes abortion, in 2012. He published anecdotes from seven women who had changed their minds after taking one of two pills to terminate their pregnancies.

5 states have adopted a version of this legislation

- Idaho is the latest

- Utah

- South Dakota

- Arizona

- Arkansas

Delgado’s new paper

Delgado has data on a new, larger group of women.

His paper — appearing Wednesday in Issues in Law and Medicine, a journal with ties to an antiabortion group — looks at 754 patients who called an informational hotline in the United States from 2012 to 2016 after taking mifepristone, the first drug in a medical abortion, but before taking misoprostol, the second drug.

While his latest research suffers from some of the same weaknesses as his previous work, such as the fact that it consists only of observational case studies rather than being part of a rigorous clinical trial, it provides numbers sure to add to the abortion debate.

The women who called the hotline were referred to doctors who prescribed them progesterone, a hormone produced in the ovaries that helps prepare the tissue lining of the uterus for pregnancy and can be given orally, by injection or vaginally.

Of the 547 patients who took progesterone within 72 hours of taking mifepristone and had outcomes that were known, there were 257 live births. Another four women remained pregnant with what seemed to be viable fetuses, but were lost to follow-up tracking after their 20th week of pregnancy. The overall rate of a pregnancy continuing, Delgado wrote, was 48 percent.

Fifty-seven of the women changed their minds again after taking progesterone. They took the second pill to complete a medical abortion or sought a surgical abortion — lending insight into just how difficult the decision process can be for some women.

Delgado concludes that the use of progesterone to stop a medical abortion “appears to be both safe and effective.”

Critics of this claim

The laws have alarmed many medical groups, including the American College of Obstetricians and Gynecologists, which says no “credible” evidence supports the idea of reversing a medical abortion.

Daniel Grossman, a professor at the University of California at San Francisco who focuses on reproductive health issues, has been one of the most vocal critics of abortion-reversal laws. Grossman, whose research focuses on improving access to safe abortion in the United States and other parts of the world, says “it makes some biological sense” that flooding the body with progesterone could counter the effect of the first abortion pill. But, he continues, there’s also logic to the argument that progesterone is elevated in a normal pregnancy and so a pharmaceutical dose won’t make much difference.

In addition, he said, “mifepristone by itself is not a very effective abortion-causing agent. If you use it just by itself there’s a good chance the pregnancy will continue on its own.” Indeed, his own work has shown that women who took only mifepristone had a 25 percent chance of the pregnancy continuing. Such a finding is why the second abortion pill is typically given.

“The really concerning part for me is that states are passing laws and essentially forcing physicians to inform women about a treatment that is experimental,” he said. Only a small fraction of the roughly 150,000 U.S. women who have medical abortions annually change their minds, he noted. “But it’s not zero, and I do think that women who change their minds should be given the best available information about what they should do.”

Grossman says it’s too soon to draw any conclusions from Delgado’s latest paper.

Delgado, who is on the board of the American Association of Pro-Life Obstetricians and Gynecologists, agrees that more research needs to be done. Once he secures funding, he said, he hopes to begin a randomized clinical trial in the next few months.

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