San Francisco ? The first of three trials testing the constitutionality of a federal ban on so-called “partial-birth abortions” ended Friday, with lawyers for abortion providers insisting the law will deny women medically necessary options and the government condemning the procedures as cruel and ghastly.

U.S. District Judge Phyllis Hamilton took the case under submission after three weeks of testimony. She will decide the constitutional question in a ruling that could take months and eventually might reach the U.S. Supreme Court.

The trial here was launched simultaneously with trials in New York and Nebraska on March 29 in a concerted campaign to overturn the first abortion prohibition since the U.S. Supreme Court upheld a woman’s right to terminate her pregnancy more than 30 years ago. The other two trials have not concluded.

Some observers view the issue in political terms. They say the law is part of multi-pronged effort to outlaw abortion by the Bush administration.

Lawyers who oppose the new federal law focused their arguments Friday on the health needs of women and the reluctance of many doctors to provide second-trimester abortions if they could face two years in prison for performing certain procedures.

A “partial-birth abortion” or what doctors call an “intact dilation and extraction” involves partially removing a nonviable fetus and puncturing its head.

Ninety percent of abortions are performed during the first trimester, which the federal law does not effect.