Imagine this situation: A woman misses her period and worries she might be pregnant. She doesn’t want to be, so she schedules an appointment with a health care provider and tells them she wishes to get her period back. The provider prescribes her a course of “period pills.” She gets her period again, and that’s the end of it.

Such a scenario is not purely hypothetical. Period pills are the same ones used in medication abortion—misoprostol alone or in combination with mifepristone—which could imply that menstrual regulation is just another name for early abortion. But the drugs might not be considered abortion medication because the patient never learns whether they were pregnant in the first place.

A recent episode of the NPR podcast Invisibilia explored the ambiguity at the root of such “menstrual regulation.” The discussion has gained momentum in the U.S. in the past five years mostly because of the increased threats to abortion rights, says Cari Sietstra, director of the Period Pills Project, which supports providers and organizations offering this intervention. And it could be one strategy for restoring reproductive autonomy in the wake of the Supreme Court’s decision to overturn Roe v. Wade.

Decline and Revival of Menstrual Regulation

The practice of menstrual regulation is not new. A 1972 article in Time noted that the procedure, then referred to as “menstrual extraction,” was “becoming medically respectable.” The article said that “more and more physicians are studying it as a possibly practical method of avoiding the legal and physical hardships of abortions done later in pregnancy.” At the time, modern abortion medications were not available, and the technique was performed by aspirating the contents of the uterus through a tube. With the 1973 Supreme Court decision affirming the right to abortion and the popularization of home pregnancy tests, the practice gradually fell out of use.

Sietstra says that, recently, reproductive health researchers working in countries where menstrual regulation is still a common practice, such as Bangladesh, started wondering if that option would resonate in the U.S.

Research confirmed that people in this country were open to the idea. A survey of those seeking a pregnancy test at nine U.S. health centers found that, among those who said they would be unhappy if pregnant, 70 percent would be interested in receiving period pills. The results were published in 2020 in the journal Contraception. In addition to potentially alleviating the stigma around abortion, period pills allow people to act quickly, even if their period is late by only a couple of days.

It is not clear how widespread menstrual regulation is in the U.S. at the moment. The Period Pills Project website has a nonexhaustive list of providers that openly offer this type of care. “Our assumption is that this is still a relatively new concept for physicians and medical providers,” Sietstra says.

Physician Michele Gomez, a provider of period pills in California, says she first learned about menstrual regulation from Sietstra about a year or two ago, and “it blew [her] mind” to think that there was room for ambiguity in pregnancy. “I knew how mifepristone and misoprostol worked, from my many years of using them for medication abortions, and I knew how safe they were, so there was no reason not to start using them as period pills right away,” she says. It’s common for doctors to prescribe medications “off-label,” using them in a way the U.S. Food and Drug Administration did not originally approve them for.

Are Period Pills Safe and Effective?

Two ongoing clinical trials are evaluating the use of period pills in the U.S. One led by Gynuity Health Projects is testing misoprostol in combination with mifepristone. And one led by the University of California, San Francisco, is testing misoprostol alone. The primary goal of both trials is to check if people with a missed period are interested in menstrual regulation and if they are satisfied with the experience afterward. “We know that for some physicians, that will be an important piece of whether or not they’re comfortable prescribing it,” Sietstra says. The studies are still recruiting patients, so it’s not clear when results will come out.

Safety and efficacy are only listed as secondary goals in the trials, mainly because the medical literature has sufficient evidence supporting the use of those pills for medication abortion, says Jennifer Ko, one of the managers of the U.C.S.F. study and a project director at the Advancing New Standards in Reproductive Health (ANSIRH) research program. The FDA has approved the use of misoprostol in combination with mifepristone to end pregnancies up to 70 days after a patient’s last menstrual period. Misoprostol alone is not approved by the FDA for this indication, but guidelines by the World Health Organization state that misoprostol can also be used alone to end a pregnancy.

The difference when the pills are used for menstrual regulation is that the patient might not be pregnant. Studies show that misoprostol has been widely used in nonpregnant people (its main indication is gastric ulcers). “If someone were to take [misoprostol], and they weren’t pregnant, their symptoms would be very mild,” Ko says. “There might be some discomfort in terms of cramping, or they might not feel anything at all.” As for mifepristone, tolerance studies have shown that it is safe when taken by healthy nonpregnant individuals even at doses much higher than those prescribed for abortion.

Sietstra says that one question she often gets from physicians is “If they can tell someone whether or not they’re pregnant, shouldn’t they just go ahead and do it?”

“I think many people in the U.S., especially some medical professionals, are reluctant to accept this notion of pregnancy ambiguity. Especially given the widespread availability of at-home pregnancy tests, they see one’s pregnancy status as clearly binary: one is either pregnant or not,” says Suzanne Bell, an assistant professor at the Johns Hopkins Bloomberg School of Public Health. She’s an author of an article published in April 2021 in Population and Development Review, where she and her co-author introduced the concept of productive ambiguity in fertility research.

Bell argues that the uncertainty that arises from the lack of pregnancy confirmation can be empowering in situations where pregnancy is not the desired outcome. This ambiguity opens different possibilities for how an individual could deal with a late period, including menstrual regulation.

A Legal Limbo

Samantha Gogol Lint was a law student at Harvard Law School in 2019 when she became interested in menstrual regulation and how it might fit into the legal system. “As the topic was still relatively fringe but starting to pick up speed, it seemed great to get into the research [then],” Lint says.

She concludes that from a legal perspective, menstrual regulation cannot be labeled as abortion. “Looking at how the courts have described abortion, I noticed that a piece that seemed to always be there was ‘knowledge of a confirmed pregnancy’ or ‘intent to end a confirmed pregnancy,’” Lint says. By definition, menstrual regulation doesn’t rely on a confirmed pregnancy.

Menstrual regulation also doesn’t perfectly fit the concept of contraception. “It is definitely further down the line of the spectrum of available means to control reproduction,” Lint says. She believes that a third category—something in between contraception and abortion—would be most appropriate for the practice.

In states where abortion is legal, menstrual regulation is clearly also legal, according to Lint. And even in states where abortion is illegal, there’s no rule against a medication to treat a late period when the patient’s pregnancy status is unknown. “There is no law banning or restricting menstrual regulation as such,” Lint says.

Considering that providers in some of those states are reporting problems accessing those medications even for nonabortion reasons, however, it’s not clear how comfortable they would be with offering menstrual regulation. “It’s quite possible that this would initially fall into a gray area that might not legally count as an abortion, but state legislators would be very likely to amend laws to also make period pills illegal,” Sietstra says.

At the same time, she hopes that menstrual regulation can shift the polarized abortion discussion. Embracing menstrual regulation could be a way for conservative states to give health care providers some room to act. “Even very conservative states will need to find some way to cope with the fallout of making abortion illegal in such strict ways that they put things like miscarriage management and ectopic pregnancies into a category where physicians are afraid to act,” Sietstra says. “This is bound to lead to very poor public health outcomes.”