The US House of Representatives have approved a measure restricting abortion to the first 20 weeks after conception.
The Pain-Capable Unborn Child Protection Act passed the chamber 228-196, largely along party lines, but the symbolic legislation stands no chance of becoming law in President Barack Obama's administration.
On Monday, the White House threatened a veto of the bill, dismissing it as "an assault on a woman's right to choose."
House Speaker John Boehner, however, hailed it as "a strong statement that all life is precious," and he noted that it comes after doctor Kermit Gosnell was convicted for illegally performing late-term abortions in his clinic.
"We have a moral obligation to defend the defenseless, and we will continue to fight to ensure our nation's laws respect the sanctity of unborn human life," he said.
The bill, which includes an exemption for women who become pregnant through rape or incest provided they first report the assault to authorities, caused heated debate in the House.
Republican congressman and long-time abortion rights opponent Trent Franks, the bill's sponsor, provoked outrage last week when he said in a committee hearing that "incidence of rape resulting in pregnancy (is) very low."
Democrats slammed Franks and Republican supporters of the bill, which also earned six Democratic votes, as being out of touch with women's issues.
Most US states allow abortions to the point when a fetus becomes viable outside the womb, considered to be some 24 weeks of pregnancy.
Ten states have passed laws similar to the Franks bill, and several of them are facing challenges in court.