Arizona Governor Doug Ducey signed a law on Monday that requires doctors to tell women that drug-induced abortions can be reversed and that blocks the purchase of insurance on the Obamacare health exchange that includes abortion coverage.

The Republican governor made good on a pledge to Arizona residents to defend the "right to life" in a continuation of former Gov. Jan Brewer's tough stance against abortion.

The bill, by Republican Sen. Nancy Barto, of Phoenix, is designed primarily to bar women from buying a policy through the federal insurance marketplace that covers abortions.

About 75 percent of the more than 200,000 Arizona residents who bought insurance policies on the marketplace get a subsidy, according to the latest federal statistics. There's no breakdown by age or sex, but even those women who don't take subsidies will not be able to get abortion coverage when the bill becomes law.

The legislation does contain an exception allowing insurance in cases of rape, incest and when a woman's life is endangered.

The requirement that patients be told that the effects of abortion pills may be undone by using high doses of a hormone was the most hotly contested provision of the bill during legislative debate.

Supporters said there was ample evidence the reversal was possible if acted upon quickly, although they provided no peer-reviewed studies in support of their position.

An anti-abortion doctor, Dr. Allan Sawyer, had testified that he recently reversed a drug-induced abortion at 10 weeks but acknowledged the procedure is not widely known.

Sawyer said doctors can give a woman a drug known as progesterone to stop an abortion after she has taken the first of two medications needed to complete the procedure.

Dr. Kathleen Morrell, an abortion doctor and advocate at Physicians for Reproductive Health, said the procedure is not evidence-based and has not been well-researched. Other critics called the argument for reversal "junk science."

Advocates on both sides of the issue said the requirement to tell patients an abortion by medication can be reversed is first time such a provision has passed in the United States. The bill cleared the Republican-controlled Legislature last week, largely along party lines.

Ducey didn't comment on the requirement that women be told drug-induced abortions can be reversed.

He said in a statement that he signed the bill to prevent taxpayer subsidies from being used to fund abortions.

Opponents said there was no proof public dollars had been used for the elective procedures and called the measure an overreach.

Bryan Howard, president of Planned Parenthood Advocates of Arizona, said the bill's signing again put Arizona in a bad light for "interfering in the medical decisions of women," and vowed to keep opposing the law through "all of our options, including litigation."

In December, the U.S. Supreme Court blocked Arizona from enforcing a state law that restricted access to abortion-inducing drugs by prohibiting off-label uses of RU-486, known as the "abortion pill."

Wire services