The Senate voted Friday to require a parent be notified before teenage girls can obtain an abortion at most hospitals.

The requirement was added to a big appropriations bill covering the Department of Health and Human Services and other agencies, which awaited a final vote.Separately, the Senate also rejected an amendment by Sen. Jesse Helms, R-N.C., to slash new federal spending on AIDS.

The Senate approved the abortion-notice requirement offered by Sen. William Armstrong, R-Colo., on a voice vote after opponents failed on a tie 48-48 vote to table, or kill, it. A tie vote meant the motion to table did not pass.

The provision, which has not yet gone before the House, would cover abortions for girls under the age of 18, performed at any hospital that receives Medicaid or other federal money.

If enacted, the provision would be the first federal requirement that parents be involved in abortion decisions by young people, although many states have passed laws requiring notice or consent by a parent or parents. Many of the state laws have been invalidated by court decisions.

Sen. Tom Harkin, D-Iowa, who led the fight against the provision, argued that it was probably unconstitutional and would effectively cover any public hospital in the country.

"I can't think of any hospitals that don't receive some Medicaid funding," Harkin said.

Armstrong's amendment was added to a provision banning Medicaid abortions for poor women, except when the life of the mother is threatened or in cases of rape or incest.

President Bush vetoed the spending bill last year because he opposed allowing Medicaid abortions in any cases other than when the mother's life is in danger.

That abortion language has been the object of yearly congressional battles. Abortion rights supporters won House passage of the broader exemption for the first time last year, then fell 51 votes short of overriding Bush's veto.

The Senate's latest version, covering spending in fiscal 1991, would allow federal money for abortions in cases of rape and incest that was "reported promptly to a law enforcement agency or public health service." The bill must go back to the House for concurrence.

Harkin's support for abortion rights is an issue in his re-election battle this year against anti-abortion Republican Rep. Tom Tauke.

Harkin complained that Armstrong's amendment contained no provision permitting so-called "judicial bypass," allowing young women who were the victims of rape or incest, or otherwise unable to discuss the subject with their parents, to petition a court for permission to obtain an abortion.

But young women with enough money could pay for abortions at private clinics that receive no federal funding and thus avoid notifying their parents.

"What this amendment provides is a two-class system," Harkin said. "The end result of this amendment is very cold and very heartless."