The US state of Iowa has approved an abortion law banning most abortions once a foetal heartbeat is detected.
Republican lawmakers passed the bill in back-to-back votes, sending it to the governor’s desk to sign into law.
If it comes into effect the bill will ban most abortions after six weeks of pregnancy, and rights groups say it will be the country’s most restrictive.
Critics argue it makes having an abortion illegal before most women even realise they are pregnant.
Iowa’s Republican governor Kim Reynolds has not said if she will sign the bill.
Republican Representative Shannon Lundgren told local media this week that she believes the bill will become law.
“We’re in the majority for a reason and that includes advancing the pro-life cause,” Ms Lundgren told the Waterloo-Cedar Falls Courier.
Last year, Iowa Republicans successfully banned abortions after 20 weeks of pregnancy.
“We are alive when our hearts start beating and our life is over when it stops,” Dawn Pettengil, another Republican Representative from Iowa, told CBS News.
Democratic Representative Beth Wessel-Kroeschell spoke against the legislation on the floor of the Iowa House of Representatives on Tuesday.
“All women, regardless of age, income or race, should be able to obtain reproductive health services, including abortion, free from political and economic barriers,” Ms Wessel-Kroeschell said.
Other Iowa Democrats called the bill “intentionally unconstitutional”.
The US abortion debate: Both sides speak
If Ms Reynolds signs the bill into law, it will likely be challenged in court for possibly violating Roe v Wade, the US Supreme Court ruling that legalized abortion in 1973. The ruling states some women have a right to terminate pregnancies until a foetus is viable.
Some Republican lawmakers welcomed the challenge.
“I would love for the United States Supreme Court to look at this bill and have this as a vehicle to overturn Roe v. Wade,” Republican Senator Jake Chapman said.
Democrats, however, say the legal costs would be a waste of tax funds.
Iowa’s Planned Parenthood and the American Civil Liberties Union groups have also spoken out against the bill.
Planned Parenthood released a statement in February, when the bill was first introduced.
“These extreme attempts to ban abortion fly in the face of both medical and legal standards, as well as common sense and public opinion among Iowans,” said Erin Davison-Rippey, Planned Parenthood of the Heartland’s director of public affairs in the online statement.
“So-called ‘heartbeat protection’ bills are actually bans on safe, legal abortion, and they threaten to set reproductive rights back by decades.”
Elizabeth Nash, of the sexual and reproductive health policy group the Guttmacher Institute, told the BBC this was “the most restrictive abortion ban in the country”.
The first draft of the bill did not include exceptions for cases of rape or incest, but Republicans added amendments on Tuesday.