The Trump administration last year reinstated — and expanded — a rule banning family planning clinics that get aid money from the United States from performing abortions or even discussing abortion with their patients. Often called the “global gag rule,” it’s led to clinic closures and reductions in crucial services around the world. And now it might be coming to the United States.

The White House is reportedly considering a domestic gag rule that would essentially apply the restrictions of the global rule to providers that receive federal Title X funds, which help low-income patients get services like contraceptive counseling and testing for sexually transmitted infections. Such a rule would force Planned Parenthood and other reproductive health providers to either stop discussing abortions with their patients or stop receiving Title X money.

The global gag rule, also called the Mexico City policy, has been reinstated by every Republican president since Ronald Reagan established it in 1984, but a domestic gag rule was only in effect for one month, in 1992. But anti-abortion groups and members of Congress have been pushing the White House to issue its own version, which some believe could come this month.

It’s not yet clear exactly what form a domestic gag rule from the Trump administration would take. The previous attempt at one was immediately challenged in court. But reproductive health advocates say the consequences of such a move could be dire — forcing doctors to lie to patients, undermining medical ethics, and leaving low-income Americans without necessary health care. On May 14, over forty senators, including Sens. Elizabeth Warren (D-MA) and Bernie Sanders (I-VT), sent a letter to the Department of Health and Human Services warning of the potentially disastrous impact of a domestic gag rule; more than a hundred members of the House sent a similar letter.

A domestic gag rule would also be part of a larger pattern in the Trump administration, which has moved repeatedly over the past year and a half to restrict Americans’ access to contraception, abortion, and accurate information about their health.

Abortion opponents have been advocating for a domestic gag rule for a while. Trump is reportedly listening.

The Reagan administration issued a domestic gag rule in 1988, but it was immediately challenged in court by reproductive health groups. The case ultimately made it to the Supreme Court, which decided in 1991 that the rule could go into effect. It took effect briefly but was again blocked by a court challenge, and when President Clinton took office in 1993, he suspended the rule. That was the end of it. until now.

Anti-abortion advocates have long been pushing the Trump administration to implement a domestic version of the global gag rule. In April, Republican Reps. Ron Estes (KS), Vicky Hartzler (MO), and Chris Smith (NJ) circulated a letter in the House asking the Department of Health and Human Services to implement such a rule, according to the Hill. “The Title X Family Planning Program is in dire need of review and updated regulations that ensure program integrity with respect to elective abortion,” the letter said.

On May 1, leaders of a variety of anti-abortion groups, including the Susan B. Anthony List and the Family Research Council, sent a similar letter to HHS. “For far too long the Title X Family Planning Program has been integrated with abortion centers,” that letter stated. “It is time to act swiftly to disentangle abortion centers from the Title X network.”

The Trump administration appears to be listening. In April, a White House aide told Modern Healthcare that a new rule on Title X would be coming in early May. And according to Axios, Kellyanne Conway met with Trump in late April to urge him to cut off Title X funding to Planned Parenthood.

The White House has not responded to Vox’s requests for comment on Title X plans. But a conservative leader told Axios that if Trump failed to take action on Title X, it would be “political suicide,” given Trump’s campaign promise to strip federal funding from Planned Parenthood.

Congressional Democrats have been vocal in their opposition to a gag rule. On May 14, 45 senators, including Sens. Warren, Sanders, Maggie Hassan (D-NH), and Patty Murray (D-WA) sent a letter to HHS warning that “a ‘domestic gag rule’ would have a devastating impact on the overall Title X network and the millions of individuals who rely on it for care.”

“Unintended pregnancy rates in the U.S. — including those among teenagers — have been declining,” the senators wrote. “We cannot threaten to reverse this progress by crippling Title X.”

More than a hundred members of the House, including Reps. Crowley, Nita Lowey (D-NY), and Barbara Lee (D-CA) sent a similar letter to HHS on the same day.

The effects of the rule would go way beyond abortion

Signed into law by Republican President Richard Nixon in 1970, Title X is the only federal funding stream dedicated solely to family planning services, said Kinsey Hasstedt, a senior policy manager at the Guttmacher Institute. Funds from the program go to health centers around the country — Planned Parenthood affiliates, Health Department centers, clinics operated by hospitals, and more — to help them offer services like contraceptive care, STI screenings, and Pap tests.

Today, about 4,000 clinics get Title X funds, and they serve about 4 million patients. Title X funding is mandated to focus on patients who are low-income or uninsured, or otherwise have difficulty getting health care, Hasstedt said, and two-thirds of patients who get care through the program live at or below the federal poverty line.

Providers are already barred from using Title X funds to pay for abortions, though they can still offer the procedure if they use other funding to pay for it.

While it’s not clear what the specific details of a Trump domestic gag rule would be, reproductive health groups think it would probably bar health centers that get Title X funds from performing abortions, referring patients elsewhere for abortions, or discussing abortion as a possible option when a patient has an unplanned pregnancy.

This would put the health of low-income patients at risk in several ways, Hasstedt said. First, it would exclude from the Title X program any providers that offer abortions. These providers, which include but aren’t limited to Planned Parenthood, are more likely than others to specialize in reproductive health, Hasstedt said. They are also more likely than others “to offer really high-quality family planning services and to serve a really high volume of Title X clients,” she explained.

Planned Parenthood, for instance, operates about 500 clinics that receive Title X money, according to Axios, but these clinics serve a disproportionate share of Title X patients — around 41 percent, the group says. According to a Guttmacher analysis, if Planned Parenthood were excluded from Title X, other Title X providers would have to increase their caseloads by an average of 70 percent in order to pick up the slack. In practice, excluding Planned Parenthood and other providers could mean some patients simply go without contraceptive care, STI screenings, and other crucial health services.

Meanwhile, providers who don’t perform abortions would be barred from talking about the procedure with their patients. This would put doctors and other health care workers in a difficult position: If a patient with an unplanned pregnancy asks about her options, they’d have to omit abortion from the list. And if she asks specifically whether she can get an abortion, they’d have to say no or refuse to discuss the issue.

“This kind of attack,” Hasstedt said, “goes after people’s ability to make informed decisions about their own reproductive health care and directly undermines medical ethics.” A gag rule “would force doctors and nurses to lie to their patients across the country,” said Dawn Laguens, executive vice president of Planned Parenthood Federation of America, in a statement to Vox.

The rule would essentially create a tiered system of reproductive health care, in which people with private insurance would be able to get a full range of information and services, and Americans relying on Title X would not, Hasstedt said. That system “would disproportionately harm folks who are low-income, people who are uninsured, people of color,” she added.

The American College of Obstetricians and Gynecologists and the American College of Physicians have also voiced opposition to a domestic gag rule. “We are deeply concerned about anticipated changes to Title X, which move away from science-based principles and erode standard of care by interfering in the patient/provider relationship,” said Hal Lawrence, the executive vice president and CEO of ACOG, on a press call last week. “We don’t need the government interfering in the exam room.”

While the contexts are different, research on the past effects of the global gag rule could offer a preview of what’s in store. The rule has forced health organizations to reduce services and close clinics around the world, according to a 2017 op-ed in the Lancet by Ann M. Starrs, the president of Guttmacher. The policy also reduced contraceptive availability in some areas, and may even have contributed to higher abortion rates.

A domestic gag rule, if it is released, would be part of a larger drive by the Trump administration to restrict access to comprehensive reproductive health care. That drive includes the administration’s weakening of the contraceptive coverage mandate in the Affordable Care Act, efforts by the Office of Refugee Resettlement to bar unaccompanied minors from getting abortions, new rules privileging teen pregnancy prevention programs that promote abstinence, and more.

“This isn’t just about the domestic gag rule,” Hasstedt said. “This is about social conservatives’ broader, and at this point relentless, assaults on reproductive health and rights.”