The federal government on Thursday permanently lifted a major restriction on access to abortion pills. It will allow patients to receive the medication by mail instead of requiring them to obtain the pills in person from specially certified health providers.

The decision, by the Food and Drug Administration, comes as the Supreme Court is considering whether to roll back abortion rights or even overturn its landmark 1973 decision in Roe v. Wade that made abortion legal nationwide.

The F.D.A.’s action means that medication abortion, an increasingly common method authorized in the United States for pregnancies up to 10 weeks’ gestation, will become more available to women who find it difficult to travel to an abortion provider or prefer to terminate a pregnancy in the privacy of their homes. It allows patients to have a telemedicine appointment with a provider who can prescribe abortion pills and send them to the patient by mail.

Earlier this year, for the duration of the pandemic, the F.D.A. temporarily lifted the in-person requirement on mifepristone, the first of two drugs used to end a pregnancy. The decision to make this change permanent is likely to deepen the already polarizing divisions between conservative and liberal states on abortion. In 19 states, mostly in the South and the Midwest, telemedicine visits for medication abortion are banned, and these and other conservative states can be expected to pass other laws to further curtail access to abortion pills.

Yet other states, like California and New York, which have taken steps in recent years to further solidify abortion rights, are expected to increase the availability of the method and provide opportunities for women in states with restrictions to obtain abortion pills by traveling to a state that allows them.

“It’s really significant,” said Mary Ziegler, a law professor at Florida State University. “Telehealth abortions are much easier for both providers and patients, and even in states that want to do it, there have been limits on how available it is.”

So far this year, presumably in anticipation of such a decision, six states banned the mailing of pills, seven states passed laws requiring pills to be obtained in person from a provider, and four states passed laws to set the limit on medication abortion at earlier than 10 weeks’ gestation, said Elizabeth Nash, the interim associate director of state issues for the Guttmacher Institute, a research organization that supports abortion rights.

The current practice is that women who live in states that don’t allow telemedicine for abortion must travel to a state that does — although they don’t have to visit a clinic. They may be in any location within that state for their telehealth visit, even a car, and may receive the pills at any address in the state.

But legal experts said they expected supporters of abortion rights to try to find ways to make the pills available without requiring a patient to travel, including possibly filing legal challenges to state laws banning telemedicine for abortion.

In data released last month by the Centers for Disease Control and Prevention, 42 percent of all abortions — and 54 percent of abortions before 10 weeks — occurred with medication in 2019, the most recent year for which C.D.C. data is available. (The report represents most of the country, but does not include data from California, Maryland and New Hampshire.)

In 2020, some states, including Indiana, Kansas and Minnesota, the method accounts for a majority of abortions, according to state health department reports.

The C.D.C. also reported that 79 percent of all abortions occurred before 10 weeks’ gestation, suggesting that there are many more women who might choose abortion pills over an in-clinic procedure if they could.

Medication abortion, a two-drug regimen, was approved in the United States in 2000. The F.D.A. imposed restrictions on the first drug, mifepristone, requiring that it be dispensed in clinics or hospitals by specially certified providers, who must sign a specific agreement and obtain the patient’s signature on a form acknowledging that their provider has informed them about the drug. The rules allowed patients to take mifepristone in their homes or anywhere they chose, making it the only drug that the agency required patients to obtain in person from a medical provider but are not required to take under medical supervision, experts say.

The second drug, misoprostol, which is taken up to 48 hours after the first, has long been obtainable with a regular prescription at a pharmacy.

Mainstream medical organizations and abortion rights groups have long urged the government to ease restrictions on mifepristone, citing data indicating that mifepristone is effective and safe, including when dispensed by mail.

For example, a research program that the F.D.A. allowed to provide telemedicine consultations and send pills by mail reported that 95 percent of the 1,157 abortions that occurred through the program between May 2016 and September 2020 were completed without requiring any follow-up procedure. Patients made 70 visits to emergency rooms or urgent care centers, with 10 instances of serious complications, the study reported.

Early in the coronavirus pandemic, medical groups filed a lawsuit asking that the in-person dispensing requirement be lifted because the pandemic meant that patients faced greater risk of being infected with the coronavirus if they needed to visit clinics to obtain abortion pills. A judge granted the request that summer, but, after a challenge by the Trump administration, the Supreme Court reinstated the restriction.

In March, medical organizations tried again, writing to President Biden and Vice President Harris. In April, the F.D.A. decided not to enforce the in-person requirement for the duration of the pandemic, allowing pills to be mailed. The new F.D.A. decision makes the suspension permanent.