The Supreme Court upheld the nationwide ban on a controversial abortion procedure Wednesday, handing abortion opponents the long- awaited victory they expected from a more conservative bench.

The 5-4 ruling said the Partial Birth Abortion Ban Act that Congress passed and President Bush signed into law in 2003 does not violate a woman's constitutional right to an abortion.

The opponents of the act "have not demonstrated that the Act would be unconstitutional in a large fraction of relevant cases," Justice Anthony Kennedy wrote in the majority opinion.

The decision pitted the court's conservatives against its liberals, with President Bush's two appointees, Chief Justice John Roberts and Justice Samuel Alito, siding with the majority.

Justices Clarence Thomas and Antonin Scalia also were in the majority.

It was the first time the court banned a specific procedure in a case over how—not whether—to perform an abortion.