A bill banning almost all abortions after 20 weeks is expected to pass the Republican-controlled House, but it has no chance of becoming a law anytime soon.
The Democratic-led Senate plans to ignore the Pain-Capable Unborn Child Protection Act, and the White House has already issued a veto threat.
Still, the legislation could set the stage for a future challenge to Roe v. Wade, the 1973 U.S. Supreme Court decision tbat created a woman's right to abortions up to the age of viability - about 24 weeks.
The sponsors of the pro-life measure cited evidence that pre-born babies can feel pain after five months.
National Right to Life Committee Legislative Director Douglas Johnson said it was the "most significant piece of pro-life legislation to come before the House since the Partial-Birth Abortion Ban Act" enacted in 2003.