Culminating an eight-year battle that featured two presidential vetoes, Congress is poised again to ban doctors from carrying out a procedure for terminating pregnancies that opponents call partial birth abortion (search).

President Bush says he will gladly sign the current legislation.

It would be the first federal law banning a specific abortion procedure since the 1973 Supreme Court ruling that women have the right to an abortion.

The House could take up the compromise bill as early as Thursday, with the Senate expected to act by mid-month, sending it to the president's desk for his signature.

House and Senate negotiators quickly reached the compromise Tuesday after stripping out a provision, added by the Senate when it passed the measure in March, that expressed support for the 1973 Roe v. Wade (search) decision. The House bill, approved in June, did not include such language.

All six Republican negotiators voted for the bill, while the four Democrats opposed it.

"Basic human decency has prevailed," Senate Judiciary Committee Chairman Orrin Hatch (search), R-Utah, said. The procedure "is never medically necessary, it is never the safest procedure available, and it is morally reprehensible and unconscionable."

But opponents expressed confidence that the bill, like similar state laws, would be overturned by court challenges.

"I wonder why we are even bothering to pass a bill that is so clearly unconstitutional," said Sen. Dianne Feinstein, D-Calif. The clear aim, she said, was to use the legislation to erode support for Roe v. Wade. "Bit by bit, what's happening is a pushing back of the clock to the way the nation was 30 years ago."

Partial birth is not a medically accepted term, but as defined by the bill it is a procedure in which the fetus is killed after the entire fetal head is outside the body of the mother or, in the case of breech presentation, "any part of the fetal trunk past the navel is outside the body of the mother."

While there is an argument about how often such abortions are carried out, there's some agreement that it mostly occurs during the second and third trimester.

President Clinton twice vetoed similar bills emerging from Congress on the grounds that they did not provide an exception for the health of the mother.

The lack of a health exception was one reason the Supreme Court, in the Stenberg v. Carhart case of 2000, ruled that a similar Nebraska law was unconstitutional. The court, in its 5-4 decision, also said the procedure was not adequately defined.

Supporters said they had met the court's objections by tightening up the definition and providing findings in the bill to show that the procedure is never needed to protect a woman's health.

But Dr. Leroy Carhart, who successfully challenged the Nebraska law, said the language was still so vague that it could effectively rule out "all safe methods of abortion that I use as early as the 12th week" of a pregnancy. He said the measure would scare physicians away from performing what might be legal procedures and "forces me to practice unsafe medicine."

Any doctor who performs the procedure is subject to fines and up to two years in prison.

Gloria Feldt, president of Planned Parenthood (search), said the current Supreme Court would undoubtedly find the bill unconstitutional and her group and other abortion rights groups would file suit and seek an injunction against its implementation as soon as it is signed into law.

"Their strategy is that they hope it will be a different Supreme Court" by the time the case reaches that level, she said.

Jim Backlin, legislative director for the Christian Coalition (search), said that if Bush is elected to a second term he might be able to appoint one to three anti-abortion judges to the Supreme Court, tipping the court in favor of restrictions on partial birth and other forms of abortion.

"It's symbolic, but it will also be the first step toward getting other pro-life legislation passed," he said.