In the six months after the US supreme court overturned Roe v Wade, roughly 26,000 more Americans used pills to induce their own at-home abortions than would have done so if Roe had not fallen, according to a new study.

Published on Monday in Jama, one of the leading peer-reviewed medical journals in the United States, the study comes ahead of a key Tuesday hearing at the US supreme court at which the justices will hear oral arguments in a case that could determine the future of a major abortion pill, mifepristone.

Pills are used in 63% of all abortions within the US healthcare system, and the study suggests they are being used by even more people than previously known in order to evade abortion restrictions that now blanket much of the US.

Analyzing data from abortion pill suppliers who operate outside of the US healthcare system, the study provides a rare window into the growing practice known as “self-managed abortion”. Although definitions of self-managed abortion can vary, the practice generally refers to abortions that take place outside the formal healthcare system, without the aid of a US-based clinician.

The June 2022 decision in Dobbs v Jackson Women’s Health Organization, which overturned Roe and unleashed a wave of near-total abortion bans across much of the US south and midwest, led to an explosion of interest in self-managed abortion, the study found.

“Where an abortion ban is in place, it’s very common for large numbers of people to look outside the formal healthcare setting to meet their needs,” said Dr Abigail Aiken, the lead author on the study and an associate professor of public affairs at the University of Texas at Austin. “What was once considered a very sort of marginal practice now seems mainstream.”

The supreme court will consider arguments to roll back recent measures taken by the Food and Drug Administration (FDA) to dramatically expand access to mifepristone, such as erasing requirements for people to pick up the pill in person. Those changes paved the way for US providers to start offering telehealth abortions within the formal healthcare system, including to people who live in states with abortion bans; a recent analysis found that telehealth abortions now account for 16% of all abortions.

However, regardless of what the court does, its actions will not affect the thriving market for self-managed abortion, because suppliers tend to source their pills from overseas pharmacies based in countries such as India.

“There’s not a way for the government to really police that system very effectively,” said Elisa Wells, another author on the paper and the co-director of Plan C, which runs an online database of organizations that offer abortion pills. “It’s unlikely to have much impact at all, except to maybe drive up the demand for those services.”

Wells also believes that, should the supreme court try to curtail access to mifepristone, the resulting outrage will strengthen abortion pill suppliers. “Every time there’s an egregious court decision, that fuels activists and providers for finding new routes of access to help people access pills in the United States,” she said.

Medical experts widely agree that it is physically safe to self-manage an abortion early on in pregnancy, and the World Health Organization even offers a protocol for doing so. It is also technically legal to end your own pregnancy in almost every state, including in the 16 states that have enacted near-total abortion bans. (Nevada has a law that explicitly criminalizes self-managed abortion later on in pregnancy.) Abortion bans generally target abortion providers, not patients.

However, experts have long warned that, if a prosecutor wants to punish someone for a self-managed abortion, they will find a statute that is elastic enough to use. Even before the fall of Roe, people had faced criminal consequences over alleged self-managed abortions. Between 2000 and 2020, 61 people were criminally investigated or arrested on suspicion of ending their own pregnancies or helping someone else do so, an October 2023 report found.

The study released on Monday examined the provision of pills from three different kinds of providers: community networks, which are groups of volunteers who usually offer pills free of charge; telemedicine organizations that provide pills with the aid of clinicians who are based outside the United States; and online vendors, which are straightforward businesses that simply sell pills.

The study’s authors obtained data directly from most of these sources, although the authors also used statistical modeling to estimate how many pills may be provided from other sources that did not supply data to researchers. Including those estimates, researchers reported that these suppliers provided almost 40,000 pills in the six months following the demise of Roe. Had Roe not fallen, the researchers estimated that they would have provided closer to 10,000 pills.

In the six months after Roe, suppliers provided almost 6,000 pills for self-managed abortions each month, the study found. That’s a monthly increase of more than 300% compared with before the fall of Roe. More than half of all these pills were provided by community networks.

Using past studies as well as providers’ own estimates of how often their pills were used, researchers also calculated how many more self-managed abortions took place after Roe compared with how many would have taken place had the landmark ruling survived. Ultimately, they estimated that 26,055 more self-managed abortions took place than if Roe had not fallen.

The landscape of self-managed abortion has probably changed dramatically even since the end of the period captured in the study, which ended in December 2022, Aiken and Wells said. More and more vendors have entered the marketplace, driving down the cost of pills. Community networks are seeing increased requests this year, Wells added.

The numbers in the Monday study, she said, “are the tip of the iceberg in terms of what’s happening out there”.