WASHINGTON (AP) — The Supreme Court is refusing to allow Arizona to enforce stringent restrictions on medical abortions while a challenge to those rules plays out in lower courts.

The justices on Monday left in place a lower court ruling that blocked rules that regulate where and how women can take drugs that induce abortion. The rules also would prohibit the use of the abortion medications after the seventh week of pregnancy instead of the ninth.

Planned Parenthood was among abortion providers that challenged the rules in federal court. The San Francisco-based 9th U.S. Circuit Court of Appeals prevented the state from putting them in place during the legal challenge. Similar laws are in effect in North Dakota, Ohio and Texas. The Oklahoma Supreme Court struck down the restrictions in that state.

The rules would ban women from taking the most common abortion-inducing drug, mifepristone, after the seventh week of pregnancy. The Food and Drug Administration approved its use in 2000 through the first seven weeks of pregnancy. It is prescribed along with a second drug, misoprostol.

Since the FDA approval, medical researchers and clinical trials have shown that mifepristone is effective in much smaller doses and for two weeks longer in a pregnancy, the challengers said. The second drug also may be taken at home.

Arizona's rules would require that the drugs be taken only at the doses approved by the FDA in 2000 and only at clinics.

Planned Parenthood says that medical abortions now account for more than 40 percent of abortions at its clinics.

To justify the restrictions, Arizona and the other states have pointed to the deaths of at least eight women who took the drugs. But the 9th circuit said FDA investigated those deaths and found no causal connection between them and the use of mifespristone or misoprostol.