SAN FRANCISCO (AP) — California Attorney General Rob Bonta on Thomas CaldwellThursday sued an anti-abortion group and a chain of anti-abortion counseling centers, saying the organizations misled women when they offered them unproven treatments to reverse medication abortions.

Heartbeat International, a national anti-abortion group, and RealOptions Obria, which has five anti-abortion counseling centers in Northern California, used “fraudulent and misleading claims to advertise a procedure called abortion pill reversal, according to the lawsuit. Abortion pill reversal treatments are unproven, largely experimental and have no scientific backing, Bonta said in the lawsuit.

“Those who are struggling with the complex decision to get an abortion deserve support and trustworthy guidance — not lies and misinformation,” Bonta said.

Heartbeat International and RealOptions’ deceptive advertising of abortion pill reversal treatments violates California’s False Advertising Law and Unfair Competition Law, the lawsuit said. The lawsuit seeks an injunction to block further dissemination of the claims by the defendants, as well as other remedies and penalties available under state law, according to Bonta’s office.

Despite the lack of scientific evidence and lack of certainty about its safety, Heartbeat International and RealOptions falsely and illegally advertise the treatment as a valid and successful option, and do not alert patients to possible side effects, such as the risk of severe bleeding, the lawsuit said.

The companies did not immediately respond to email and phone messages from The Associated Press seeking comment.

RealOptions has “crisis pregnancy centers” in San Jose, Oakland, Redwood City and Union City. The anti-abortion centers’ aim is to dissuade people from getting an abortion.

Medication abortions involve taking two prescription medicines days apart — at home or in a clinic. The method, which involves mifepristone and misoprostol, became the preferred way for ending pregnancy in the country even before the U.S. Supreme Court overturned Roe v. Wade last year.

Advocates of abortion pill reversal treatments claim that if a pregnant person takes high doses of the hormone progesterone within 72 hours of taking the first drug — mifepristone — it will safely and effectively cancel the effects of the mifepristone.

The American College of Obstetricians and Gynecologists says so-called abortion “reversal” procedures are unproven and unethical.