JERSEY CITY, N.J. -- At 5 on a weekday afternoon, the waiting room at the Health Services family planning center is beginning to fill up. English and Spanish-language posters warning about AIDS decorate the walls, a videotape about breast self-examination flickers on the television, and children play on the soiled avocado carpeting.

A 21-year-old Hispanic woman has come for birth-control pills following an abortion at the center a few weeks ago. A girlfriend, she says, told her it was a good place to go. "I don't know any other clinic," says the woman, who has a 1-year-old daughter. "Thank God I found my friend."

A world away from Bergen Avenue, the Bush administration is seeking to change the rules under which Health Services and some 4,000 other clinics have been operating since 1970, when the federal government launched the Title X program to subsidize family planning services for low-income women.

The Title X law bars recipients from using the federal money for abortion "as a method of family planning." But the clinics have been allowed, and since 1981 required, to provide "non-directive" counseling -- telling pregnant women their options and referring them, if they wish, to abortion providers.

Under regulations adopted in 1988 and now under review by the Supreme Court, the clinics would no longer be able to counsel or promote abortion in any way -- even if the patients ask for the information or, critics say, if their doctors believe that abortion is medically indicated. Instead, clinics must refer all pregnant patients to facilities that provide pre-natal care to "promote the welfare of mother and unborn child," according to the regulations, now in effect in parts of five states.

"I think it would be such a grave injustice to patients," said Maryann Pietrowski, a nurse-practitioner at the Health Services clinic. "How could I look at a patient I've developed a relationship with over the years and know what services were available and say, 'Sorry, I can't talk to you.' I'd feel like a fool . . . . If they met me in Shoprite I could give them more information than I could in the confines of the clinic."

To Nabers Cabaniss, the Health and Human Services official in Washington who oversees the Title X program, the regulations are simply the cost of doing business with the federal government. "If you don't like our rules, you don't have to receive our funds," she said. "We think it's totally wrong for the federal government to subsidize a woman's abortion-related service. The state's interest is in promoting and protecting innocent human life."

The challenge to the regulations, Rust v. Sullivan, will be heard by the court today and may be the only abortion-related case the justices hear this term. The case also raises important questions about the power of government to set limits on the use of its funds, the free speech rights of health-care providers and the rights of women to receive full medical information.

Underlying the legal issues are two radically different visions of what the family planning program does, and what impact the regulations would have on those it was designed to serve.

The regulations stipulate that the list of facilities to which pregnant patients are referred cannot include any clinic whose principal activity is providing abortions. If a patient asks for such a referral, the regulations suggest, she could simply be told that "the project does not consider abortion an appropriate method of family planning." There is a raging debate in the lower courts about whether clinics that accept Title X funds, now $140 million annually, could even give patients a copy of the Yellow Pages.

Programs that accept Title X funds and use separate money to provide abortions would have to segregate their activities completely, physically and financially, providing separate waiting rooms, accounting, and staff -- a requirement, opponents say, that would doom operations like Health Services, which offers contraception, abortion, obstetric and infant care and receives nearly $200,000 in Title X funds.

Administration officials say the regulations simply uphold the government's established right not to subsidize abortion-related services and to express its preference for childbirth over abortion.

"The regulations do not prevent a woman from obtaining abortion information; she simply must seek it from a source other than a Title X project," Solicitor General Kenneth W. Starr told the court in his brief.

Opponents respond that while the government can choose to subsidize some activities and not others, it cannot require that those receiving federal funds espouse a particular viewpoint -- in this case promoting the government's "ideological slant against abortion." They say the rules infringe on the due process rights of women by manipulating the doctor-patient relationship and obstructing women's ability to obtain prompt and accurate medical information.

"The decision not to pay for it does not encompass a right to suppress information about it," said Harvard Law School professor Laurence H. Tribe, who will argue today against the regulations. "Here the government is not simply declining to pay for abortion and abortion counseling but mandating distortion of what doctors in government-assisted clinics are to say to women who have come to rely on them."

Two federal appeals courts -- in Boston and Denver -- have struck down the regulations. Splitting 2 to 1, the appeals court in New York upheld them in the case now before the high court, a challenge by Planned Parenthood and the city and state of New York, which also fund family planning clinics.

An array of antiabortion groups have urged the Supreme Court to uphold the regulations and overrule Roe v. Wade, the 1973 decision that established a constitutional right to abortion. Arguing against the regulations, the American Medical Association and the American College of Obstetricians and Gynecologists contend they would force physicians to violate their medical ethics and legal obligations.

The opponents argue that Title X clinics are the primary, and sometimes the only, source of health care for many of the 5 million women -- nearly one-third of them teenagers -- who use them each year, dispensing not just contraceptives but conducting general physical examinations, checking blood pressure, testing for AIDS and other sexually transmitted disease.

The clinics, in their view, are not an option their patients elect to employ but often their sole choice. And the regulations, they contend, do not merely fail to provide information to women but steer them in one direction, mandating that women be referred for pre-natal care and imposing no restrictions at all on antiabortion rhetoric.

At times, they say, the rules entail positive harm -- for example, prohibiting a physician from informing a woman with heart disease of the strain pregnancy could put on her health, or a woman with cancer that pregnancy could accelerate the spread of tumors. (According to Cabaniss, this is a misreading of the regulations.) An appropriate comparison, the opponents say, would be ordering doctors not to tell Medicare patients about the availability of kidney dialysis machines or forbidding public defenders from instructing criminal defendants about their right to remain silent.

Administration officials argue that the government has chosen to fund a limited set of services -- pre-pregnancy family planning -- and the regulations pose, at most, a mere inconvenience for women who want abortions. The regulations do not coerce clinics to mislead their patients, the administration says, since clinics can simply offer disclaimers that they do not provide abortion information.

"Our concern is treating abortion as an equivalent choice with giving life to the child is not appropriate in a program which is clearly designed to reduce the incidence of abortion," Cabaniss said. Abortion, she said, "is the only thing the statute says we don't want any part of. Talking about abortion as an equivalent choice with giving birth is, in our view, not consistent with the statute."

At Title X clinics like Health Services here and a Planned Parenthood center known as The Hub in New York's South Bronx, doctors and counselors say the idea that women have an array of health-care choices bears no resemblance to reality.

The Hub is in a part of the Bronx that clinic director Mary Morales describes as "infected with drugs and AIDS and infant mortality;" where patients sometimes arrive high and the only alternative for many women would be a five- or six-week wait to be seen at a public hospital.

Planned Parenthood says it will forgo the Title X funds rather than comply with the restriction -- even though the loss, it warns, could imperil the existence of the clinic, which receives about $450,000 in Title X funds, 27 percent of its annual budget.

The Hub's patients, 99 percent black and Hispanic, "don't have any money. They can't go to a private doctor," said Dr. Irving Rust, the clinic's medical director and the named plaintiff in the case. "To not be allowed to give that information is just an abomination. What you're doing is giving the poor person, the black and Hispanic person, second-class care . . . You're doing the opposite of what the Hippocratic oath proposes for a physician to do."