On February 29, 2016, the FDA announced it is asking for a new clinical study about the safety of Essure, a type of permanent birth control. The agency will also require a black box warning about the device’s risks. WIRED’s original story, about how women convinced the FDA that Essure needed more oversight, is below.

The numbers were so dramatic the Food and Drug Administration couldn’t ignore them. In 2012, reports of side effects from Essure, a popular and permanent form of birth control, hovered just over 100—not great, but reasonable. But by 2014, the number of unverified reports of problems like pain, perforation, and even pregnancy with the nonsurgical tube-tying alternative skyrocketed to 2,259. What’s behind this sudden, dramatic increase? A Facebook group called Essure Problems, now over 20,000 members strong.

This Thursday, the FDA is making an unusual move, holding a public advisory committee meeting to discuss Essure, approved back in 2002. The agency is unlikely to yank the device entirely, since Essure, which is inserted into the fallopian tubes, has worked for thousands of women. But the agency can require more studies and updated labels reflecting increased risks. That the FDA called the meeting at all signals it is listening, and lately, the agency has been more interested in giving patients a voice in the regulatory process.

And patients are talking—not just to the FDA but to each other. Amanda Dykeman, an admin on the Essure Problems Facebook group, describes how the group encouraged women to file adverse event reports with the FDA, accounting for the recent jump. “A lot of women don’t know how to do that or they don’t know they’re supposed to do that,” says Dykeman. “I kind of figured once enough were filed, the FDA would take another look.” The few members of the group have also met with congressional staff and the FDA in private, which also likely influenced the agency to hold a public meeting.

Now, Dykeman and a few dozen other women in the group are traveling to DC to speak at the meeting in person. Their symptoms aren’t to be taken lightly, they say. “It’s severe, debilitating pain and bleeding that will knock you down,” says Dykeman, who received the device in 2010 and had it removed in a hysterectomy in 2013. “You can’t live your life.” Every birth control method comes with risks though, and the FDA approved Essure knowing that the device can cause problems in a small number of women. Whether this huge uptick in adverse event reports means Essure is in fact more dangerous than shown in clinical trials—paid for by Essure’s manufacturer, of course—is a major question for the FDA meeting.

The New Thing

Before Essure came under fire, it was the hot new thing in birth control. Unlike pills or patches or even IUDs, Essure is permanent. And unlike laparoscopic tubal ligation (getting your tubes tied), it doesn’t require cutting through the stomach and general anesthesia. “If the uterus is like the house, and the cervix is the doorway, with laparoscopic surgery we used to try to bust through the chimney,” says Aileen Gariepy, an OB-GYN at Yale. “It’s an easier process to go through the front door.”

Essure is a small metal and plastic coil that gets passed through the vagina, the cervix, and the uterus until it extends into the fallopian tubes—one coil in each tube. Over time, the coils cause the tubes to scar over, blocking eggs from reaching the uterus. Crucially, women have to use alternative birth control, like condoms, in the first three months after getting Essure as the scar tissue forms. Only after an X-ray confirmation are they in the clear. Not all coils stay in on the first try, and not all cause complete scarring of the tubes in just three months.

Essure’s website says the device is over 99 percent effective. “What was publicized was if if if if—if everything goes perfectly, and life isn’t perfect—it was 99 percent effective,” says Gariepy. Women have reported getting pregnant on Essure, but Bayer, which currently makes the device, chalks pregnancies up to user error, mistakes like not getting the three-month confirmation. In any case, the added complexity means that in real life, Essure is not as effective as tubal ligation, which works immediately.

Comparing the safety of tubal ligation to Essure is where things get even trickier. Good data on tubal ligation is nearly half a century old, and long-term data on Essure simply doesn’t exist. In clinical trials from Essur’s manufacturer, 2.9 percent of women reported severe menstrual cramps and 2.5 percent severe pain after one year with Essure. Perforations, in which coil poked out of tissue, occurred in 2.9 percent of women in one study and 1.1 percent in another. Then, in a five-year study that continued after the device went to market, only 71 percent of women initially enrolled in the trial were followed through the end of the study. And fifteen of those women also had hysterectomies, though the criteria for deciding whether those hysterectomies had to do with Essure are unclear.

That leaves regulators with a huge increase in adverse reports—which aren’t reliable data, but do point to some kind of trend. But what?

Enter Facebook

Angie Firmalino started a Facebook group in 2011 because she wanted a private space to talk to about Essure away from friends or relatives. The initial procedure was painful, but she says the pain, fatigue, and heavy bleeding persisted for years after. That’s when she started the group. The Facebook group grew and grew and grew until it reached the 20,000 members it has today.

Essure Problems has since grown into a non-profit, ASHES—Advocating Safety in Healthcare E-Sisters—of which Firmalino is also president. Erin Brockovich has lent her celebrity weight to the cause. And this organic movement that bubbled up through social media has joined forces with more conventional means of political organizing: Diana Zuckerman, director of the National Center for Health Research has organized meetings for Essure patients with congressional staff and the FDA. But it all started with the Facebook group. “It’s a lot easier when it’s 20,000 women than when it’s one Essure patient,” she says.

The Essure Problems community is part advocacy, part support group. It uses its own lingo that flips the pun in Essure on its head: Women chat with their “e-sisters” about “e-hell.” They support each other through hysterectomies. Amanda Rusmisell, a member of the group, is carpooling to DC this week with a woman she met through Facebook. When that woman was recovering from her surgery to remove Essure, Rusmisell went to cook her dinner.

But Essure Problems is not all positive, and a lot of anger also tinges the posts—some of it that may or may not be fairly directed at Essure. “You see everything from the real effects to sometimes people wanting to blame it for things the device has no control over,” says Charles Monteith, a surgeon in Raleigh, North Carolina, who performs Essure removal surgery. Adverse events reported to the FDA, which are unverified and can be double reported, don’t pass scientific muster as data either.

When stuck between a few trials paid for by the device manufacturer and a huge number of messy adverse event reports, the most reasonable conclusion seems to be asking for more data. The FDA seems to be considering these studies based on its discussion question for the meeting. (The agency declined an interview.) “There are known risks,” says Elizabeth Micks, a OB-GYN at the University of Washington, about Essure. “But it would be really great to have long-term data.”

Every form of birth control comes with risks. Unlike a pill which you can just stop taking though, Essure requires major surgery to remove, so getting those risks across is all the more important. That, at least, the FDA can accomplish with its public meeting.