Women’s health clinics that provide abortions or refer patients for the procedure will be cut off from a key source of federal funding under new Trump administration rules expected to be released Friday.

Both the New York Times and Modern Healthcare report that the White House plans to issue new guidelines for Title X, the only federal program dedicated to paying for birth control. The new rule is expected to require a “physical as well as financial separation” between entities that receive Title X funds and those that provide abortions.

The new rule is the latest battle in Republicans’ years-long war to end Planned Parenthood’s public funding. The women’s health provider currently uses Title X funding to provide contraceptives to millions of low-income women. Planned Parenthood estimates that it sees approximately 41 percent of women who receive family planning services through Title X.

It is true that Planned Parenthood is the country’s largest abortion provider. In 2009, the organization performed just over 330,000 abortions, about 40 percent of all abortions that year.

But it’s also true Planned Parenthood is a key part of the American health care safety net and one of the largest providers of contraceptives in the country. More than one-third of low-income women who get birth control through Title X currently do so at one of Planned Parenthood’s 817 clinics.

The best research we have suggests that if Planned Parenthood is cut out of the Title X program, there isn’t a backup option. Low-income women who use Title X services at these clinics likely will not have another place to turn for birth control — and unintended pregnancies could rise as a result.

Title X provides birth control to low-income women. Lots of those patients use Planned Parenthood.

Launched in 1971, Title X was meant to fulfill President Richard Nixon’s promise that “no American woman should be denied access to family planning assistance because of her economic condition.”

Title X does not, and has never, paid for abortions. Federal law prohibits any government dollars from paying for the termination of pregnancies. Organizations like Planned Parenthood often use Title X grants to subsidize birth control, STD screenings, and other reproductive health services for low-income patients who may lack health insurance coverage.

The program grew steadily over the past 40 years, from a $6 million budget in 1971 up to $286 million in 2017. In 2014, an estimated 4,100 clinics used Title X funding to provide low-cost or free contraception to their low-income patients, typically those who lacked health insurance coverage.

Many of those Title X patients seek care at Planned Parenthood clinics.

This is partially due to the fact that Planned Parenthood exists in many places where other family planning clinics don’t: A new analysis from the Guttmacher Institute estimates that there are 103 counties in the United States where Planned Parenthood is the only provider of publicly funded contraceptives. In an additional 229 counties, Planned Parenthood serves the majority of women who are low-income and qualify for government help paying for birth control.

Guttmacher Institute/Health Affairs

Separate research suggests that Planned Parenthood plays a unique role in catering to women’s birth control needs, providing greater access to family planning services than other clinics.

Eighty-nine percent of Planned Parenthood clinics, for example, report being able to provide their patients with emergency contraceptives, compared to 34 percent of federally qualified health clinics (which typically serve low-income patients and are also a major recipient of Title X funding). And 81 percent of Planned Parenthood clinics say they provide same-day access to intrauterine devices (IUDs), the most effective type of reversible birth control. By contrast, just 30 percent of other clinics do that.

Kaiser Family Foundation

This new rule won’t end Planned Parenthood’s federal funding completely. The clinics actually receive three-quarters of their public money through Medicaid, the federal program that covers low-income Americans.

When Medicaid patients fill birth control prescriptions at Planned Parenthood or receive certain health care screenings, the insurance program reimburses the clinics for those services. This new rule won’t change that.

Instead, cutting off these funds would likely make it harder for Planned Parenthood to provide family planning services to women who lack health insurance coverage. This would be especially acute in the 18 states that did not expand Medicaid under the Affordable Care Act, leaving their low-income residents with few options to find affordable health insurance.

States have experimented with cutting off Planned Parenthood’s funding. Unintended pregnancies have gone up.

One former Republican president, Ronald Reagan, has implemented similar restrictions around the Title X program. Regulations issued under his administration in the late 1980s prohibited Title X health centers from sharing staff or a physical location with abortion providers. Opponents of the policy dubbed this the “domestic gag rule,” as it mirrored a separate “global gag rule” that banned international family planning clinics receiving American aid money from performing or discussing abortion.

President Clinton ended those restrictions in 1993, and clinics like Planned Parenthood have received Title X funding ever since.

More recently, Texas has experimented with cutting abortion providers out of state-level family planning grants. Recent research shows that this led to fewer women getting birth control, and more unintended pregnancies.

The Texas Policy Evaluation Project at the University of Texas used pharmacy claim data to understand what types of birth control women used before and after Texas cut Planned Parenthood from its public family planning program. This is a program that serves women who earn less than $1,800 a month if they are single (or less than $2,426 per month if they have a child).

Data published in the New England Journal of Medicine demonstrated some very big changes that happened to Texas women in the counties that used to have Planned Parenthood as part of their networks.

For example: Prescriptions for long-acting, reversible contraceptives including IUDs and birth control implants plummeted by 35.5 percent in counties where Planned Parenthood clinics shuttered after the new law. When Planned Parenthood was part of the Texas program, 1,042 women used this type of birth control over the course of three months. Afterward, it was 672.

New England Journal of Medicine

The Texas women’s health program had about 8,000 women using the injectable contraceptive Depo-Provera, which requires a shot every three months for the medication to remain effective. Even before Planned Parenthood was cut from the Texas network, only 56.9 percent of patients in counties with Planned Parenthoods would return for an on-time follow-up shot every three months.

Numbers fell much lower, though, after the 2013 cuts. Counties previously served by Planned Parenthood clinics saw a 21.2 percentage point decline in women returning for on-time shots — while numbers in counties that had never had Planned Parenthood clinics essentially held steady.

New England Journal of Medicine

Less access to birth control correlated with an uptick in births among certain Texas patients.

This design of this part of the study is a bit complex, and you can read more about it in the paper itself. It essentially involves comparing women who were using the Depo shot at the end of 2012 — right before the Planned Parenthood cuts — to women who were using the Depo shot at the end of 2011 and experienced no such disruption.

Researchers found that the women who lived in places affected by the Planned Parenthood cuts had 27 percent more births than the women using Depo in the year prior.

This was not just a sudden increase in Texas women having babies. Births among women who’d never had a Planned Parenthood clinic in their county to begin with actually decreased slightly over the same time period.

“This directly contradicts the claim that other providers will simply take up the slack and that they’ll meet the demand currently being met by Planned Parenthood providers,” Amanda Stevenson, who led the Texas study, told me when it was released last year. “We can say, after this study, that isn’t the case in Texas.”