North Dakota on Tuesday adopted the most restrictive abortion law in the United States, as the governor signed a bill that bans the procedure in most cases once a fetal heartbeat can be detected, as early as six weeks.
Supporters of abortion rights said they would challenge the measure in court.
Governor Jack Dalrymple on Tuesday also signed a bill that bans abortions based solely on genetic abnormalities, the first state ban of its kind, or based on the gender of the fetus.
North Dakota is the latest state to pass measures to restrict abortions. Arkansas lawmakers earlier in March approved a ban on most abortions after 12 weeks of pregnancy that could take effect in August if it survives expected legal challenges.
Several states ban most abortions after 20 weeks of pregnancy. Critics said the ban at six weeks would take effect before many women would know they were pregnant.
Dalrymple, a Republican in a state with a Republican-controlled legislature, said the constitutionality of North Dakota's effective ban at six weeks into pregnancy was an open question. He said lawmakers should appropriate money to a litigation fund for the state attorney general to defend against any possible challenges to the law.
The "heartbeat" bill provides exceptions if an abortion would prevent the death or irreversible impairment of a pregnant woman, but provides no exception for rape. It sets up a direct challenge to the Supreme Court's decision in Roe v. Wade that legalized abortion in 1973.
"These are bills that have passed the legislature. This is what they want to do," Dalrymple said in Dickinson, North Dakota. "They have a legislative right to find out if these laws can stand."
Republican state Senator Spencer Berry, a bill sponsor, had said when lawmakers sent the bill to the governor that 40 years of medical advancements should not be ignored.
U.S. Senator Heidi Heitkamp, a North Dakota Democrat and former state attorney general, said the six-week ban and other abortion bills signed Tuesday probably were not constitutional.
"I think it's way too extreme," Heitkamp said.
The Center for Reproductive Rights said it plans to file a legal challenge to the six-week ban before it takes effect on Aug. 1 on behalf of North Dakota's only clinic that provides abortions, the Red River Women's Clinic in Fargo.
"North Dakota has set a new standard for extreme hostility toward the rights and health of women, the U.S. Constitution, and 40 years of Supreme Court precedent," Nancy Northup, the center's president and chief executive, said in a statement.
"We will not allow this frontal assault on fundamental reproductive rights to go unchallenged," Northup said.
Roe v. Wade and later Supreme Court decisions have found that states cannot ban abortions before the fetus is viable.
Dalrymple on Tuesday also signed a third bill on abortions, requiring physicians who perform abortions in the state to have privileges at a nearby hospital that also permits abortions in its facility.
North Dakota lawmakers this session also approved putting a proposed amendment to the state constitution before voters in 2014 that would define life as beginning with conception, effectively outlawing all abortions.
Similar measures have been put before voters in several states, including Mississippi, and rejected.
Planned Parenthood said Tuesday it is working with a broad group of doctors, patients, teachers, lawyers and others to oppose the proposed "personhood" amendment.