The nurse practitioner who inserted my IUD worked with the precision and speed of someone on a pit crew. Or, really—just someone working in the gynecology department of a student clinic at one of the largest universities in the U.S.

“You probably do a lot of these, huh?” I asked. She smiled.

For weeks, I had been dreading the appointment. A steady stream of friends who had endured the procedure before me had warned me it hurt. Still, they said, reliable, long-lasting birth control was worth it. Indeed, for a few seconds the procedure was excruciating—but it was over quickly.

“You’re good for five years,” the nurse told me as I left the exam room. It almost felt too good to be true.

It was, in fact, worth it. The little device fit into my life so seamlessly that I usually forgot it was there; having an IUD meant I almost never had to think about birth control. No more phone alarms for pills, or obnoxious trips to CVS. Aside from some occasional spotting, my periods stopped. Years passed. I graduated; I moved; I got engaged. The whole time, the device was in there, doing its thing.

This is the best-case scenario. But it is not the only one. Many women have severe pain during insertion. Why can’t I simply be knocked out for this process? they wonder. (It turns out, if you know who to ask, you can.) Others report negative side effects that they come to associate with their intrauterine device—acne, headaches, mood changes. Is this weird thing happening to my body because of my IUD? they ask. (In many cases, the answer is: Maybe.)

There are decades’ worth of rigorous studies that validate the safety and efficacy of IUDs. Their message is quite clear: Adverse events happen, but severe ones are rare. Pregnancy with an IUD in place happens, but again, it is very rare. The IUD is, these studies show, a stellar form of birth control.

And yet: Many women regard the IUD as a sort of poltergeist, liable to mess with everything from their temper to their appearance. One co-worker swears that an IUD caused one of her eyebrows to fall out, though she can’t prove it. Another swears it was her IUD that was responsible for her partner getting repeated yeast infections on his penis. (One doctor told her it wasn’t related. Another said it could be. It turns out the device can carry a biofilm.) And finally, when even I, a person who loves her IUD, went to get it replaced five years in, I was baffled to find out that actually, it was now good for eight years. (Cool, but … how?)

It can be hard, as an individual woman, to access clear, compassionate answers to even seemingly basic questions about one’s IUD. On one of the online forums where women go to search for those answers: “It’s so frustrating that I have to go to Reddit,” one user recently wrote, “to figure out what other people experience.” Why, when it comes to a popular form of birth control, are women sometimes made to feel like we know so little?

IUDs were not initially designed for women. They were designed to manage women.

The development of the modern IUD is inextricably linked to the population control movement, as Chikako Takeshita documents in her book The Global Biopolitics of the IUD. In the 1950s, governments, international organizations, and wealthy funders began to fret over a “population explosion in the global South,” she writes. This, in their minds, could cause all sorts of problems: hunger, environmental destruction, political unrest, communism—all the way up to nuclear war. They needed to build a device that they could strategically deploy to ensure women, in certain areas, had fewer children.

One of the key organizations pushing forward the development of such a device was the Population Council, Takeshita writes. It awarded research grants to the physicians who developed some of the earliest models, funded the first long-term study on IUD efficacy, supported distribution of devices, and organized several international conferences focused on IUDs. As Takeshita notes, at the first such gathering in 1962, the conference chairman, Alan Guttmacher, discussed the need for a contraceptive for the “masses”: Existing methods, he said, “are largely birth control for the individual, not for a nation.”

The user’s experience in early IUD development was a secondary concern, an issue only insofar as a negative experience might cause a woman to have it removed. The first large-scale comparative study on the devices ran in the ’60s and involved tens of thousands of women testing five different types of IUDs—Lippes loops, Margulies spirals, Birnberg bows, steel rings, and double coils. The researchers evaluated IUDs in three areas: pregnancy prevention (they were OK at this, but not yet amazing), accidental expulsions, and removals. Reasons for removals were slotted into four categories: “bleeding/pain,” “other medical,” “planning pregnancy,” or “other personal.” “Other medical” branched off into several subcategories, including pelvic inflammatory disease, uterus perforation, and “discomfort to husband,” among others. The categories, though, offered little detail as to the more specific symptoms that led a woman to request removal.

“This,” Takeshita writes, “made it impossible to analyze the relationship between side effects and removal in detail.” In the early distribution of the IUD, the Population Council worried that “dissatisfied women” would spread “adverse gossip” about the devices.

Soon, though, they’d have good reason to. In 1971, a new IUD came on the contraception scene: the Dalkon Shield, which was made of plastic and looked like a cross between a beetle and a crab. The idea was that the legs would brace against the uterus and prevent accidental expulsions, which was a notable problem with the other devices that were at this point being offered in clinics across the U.S. The Dalkon Shield, the New York Times would later explain in its inventor Hugh Davis’ obituary, was “hailed as a scientific marvel, a highly improved intrauterine device … promising almost perfect birth control protection with virtually no adverse side effects.” In his 1971 book Intrauterine Devices for Contraception, Davis bragged about the device’s “pregnancy protection among young, highly fertile women”; he hypothesized that the plastic device’s large surface area and close contact with the uterus would boost its effectiveness.

But the Shield wasn’t just supposed to be better at blocking pregnancy. The manufacturer, A.H. Robins Company, marketed it as “the only IUD anatomically engineered for optimum uterine placement, fit, tolerance, and retention,” and dubbed it “the IUD that’s changing current thinking about contraceptives.” In a 1972 advertisement in an OB-GYN journal, the company bragged that the Shield (in contrast to the pill) had “no general effects on the body, blood, or brain” and allowed a woman to “throw away her calendars, charts, and dispensers.” You get the IUD, the ads said, and you are simply done having to think about your fertility. IUDs may have initially been designed for population control, but for the individual consumer, they came with clear perks.

Or so Robins claimed. In reality, the beetle/crab design proved to be shockingly dangerous. It could embed into the uterine wall, and caused a great deal of pain during insertion and removal. A 1985 article from the Washington Post cites a letter from a gynecologist to the device’s manufacturer in the weeks after it was first introduced: “I have just inserted my 10^th Dalkon Shield,” he wrote, “and have found that procedure to be the most traumatic manipulation ever perpetrated upon womanhood.” Some reports note that compared to other devices, inserting the Shield took “10 times more force.”

Still, the Shield quickly came to dominate the IUD market in the U.S. Three and a half years after its introduction, some 2.2 million women in America had a Shield inserted. All told, Takeshita notes, Robins sold around 4.5 million devices in 80 countries.

Meanwhile, though, reports of pelvic inflammatory disease, septic abortions, and uterine perforations, among other adverse events, became widespread. The clearest culprit was the string used to pull the device out: The Shield used multifilament string, which essentially had the effect of “wicking” bacteria up into the uterus, where it could cause dangerous infections.

Researchers point out that, in hindsight, there are likely multiple things that went wrong—the Shield was a poorly designed, relatively untested device with a high failure rate, and was aggressively marketed during the early ’70s, a period when sexually transmitted infections were on the rise and not adequately screened for. All of these factors contributed to a greater risk that bacteria ushered in via the Shield could cause dangerous infections and septic abortions. (The company, in response, focused on blaming women for risky sexual behavior and a lack of hygiene, attempting to muddle its responsibility by pointing to the fact that pelvic inflammatory disease does not require the presence of a bacteria-wicking device.) Robins stopped selling the devices in the U.S. in 1974, was hit with a wave of lawsuits, and later filed for bankruptcy. The company eventually set up a trust fund to handle claims against it; by the time it closed in 2000, according to the University of Virginia Law Library, the fund “paid out almost $3 billion to over 218,000 claimants.” The device was linked to at least 18 deaths, and tens of thousands of infections that in many cases led to infertility.

“If you asked me to try to sell an IUD to a woman in the early 1980s, I would have told you, ‘You’re crazy,’ ” Mary Jane Minkin, a gynecologist who served as a witness for Robins in some of the claims against the company, told me. A few other companies did, indeed, stop trying, and pulled their IUDs off the market.

But in parallel, the groundwork for a much different, much more reliable IUD landscape was being laid: In 1975, the Food and Drug Administration decided to require that manufacturers include patient labeling—a brochure with information about how the device works and potential risks—with the IUD, making it the third prescription product with such a requirement. In 1976, Congress established three different classes of medical devices, which, depending on their risk level, can require premarket approval from the FDA. Today’s IUDs are actually regulated not just as devices but as drugs (because of their hormones and copper), which means they go through extensive clinical testing and regulatory review to ensure their safety and efficacy. The Shield had gone through no such process—Robins took the device to market, the New York Times reported, based on “a yearlong test of 640 women” run by Davis, the device’s inventor.

By 2002, just 5.8 percent of heterosexually active, premenopausal women had ever used an IUD, and fewer than 2 percent were currently using one. The device was, nonetheless, going to make a stunning comeback.

Just before I entered college, in 2014, the American Academy of Pediatrics decreed that IUDs and implants (like Implanon and Nexplanon) “should be considered first-line contraceptive choices for adolescents.” These devices were a far cry from the models of decades prior: much more effective, much safer, and much more tightly regulated. By the early 2010s, they had been around for a long time, and gynecologists had good reason to trust them deeply. The IUDs on the market in the U.S. are extremely effective; IUD users who choose to keep their device through its life cycle report high satisfaction rates. In a recent round of data, which looked at 2015 to 2019, 1 in 5 sexually experienced women had used an IUD. On the list of most common primary contraceptives, the device ranks third—tied with condoms and behind female sterilization and the pill, according to 2018 data.

This new IUD world was headlined by two principal T-shaped stars, both of which had emerged in the aftermath of the Dalkon Shield fiasco. In 1984, the FDA approved the Paragard, which was covered in copper. Then there was a hormonal IUD, first introduced in Finland, loaded with 52 milligrams of progressively released levonorgestrel. That device, marketed in the U.S. as Mirena, was approved by the FDA in 2000. And the Mirena and Paragard would later be joined by three other devices: the Skyla and Kyleena, smaller hormonal IUDs, and the Liletta, the functional equivalent of Mirena, developed by a nonprofit.

But the relationship many of us began to form with IUDs went beyond trusting them as a reliable form of birth control and into something else entirely. News organizations started to publish articles coronating the IUD as the “best” birth control. Some people began donning IUD jewelry. After the 2016 election, the president of Planned Parenthood gave interviews saying there had been a 900 percent increase in women seeking IUDs at their clinics. One colleague told me she got an IUD because “it felt like the right thing to do.” Another said her college classmates used to joke that if you went to the campus health center with any ailment—a stubbed toe, a cold—you would walk out with an IUD.

At this juncture, IUDs were simultaneously a form of birth control and a symbol of bodily autonomy. They were also, maybe, a little bit of a prayer; once installed in our uteruses, we hoped they could protect us from the political whims of anyone in office who was trying to curtail our reproductive freedom. The IUD continues to be both a tool and a symbol: The day the Supreme Court overturned Roe in 2022, there was a more than 375 percent increase in people scheduling appointments for IUD insertions at Planned Parenthood clinics. This year, a few weeks before the two-year anniversary of that decision, the advocacy group Americans for Contraception placed a 20-foot-tall inflatable IUD in front of Union Station in D.C. in an attempt to rally support for the Right to Contraception Act.

There are downsides to tasking medicine with doing so much. The combination of a device that is scientifically really good in a moment that is politically really scary in a sense magnetizes the IUD, pulling young women like me into line at the campus clinic, no questions asked. But that field of force also obscures an important truth: The IUD isn’t—and shouldn’t be—a blanket solution to protect everyone with a uterus through a tumultuous reproductive landscape. IUDs, like any medication, come with side effects, as well as unknowns. While modern IUDs are a far cry from the Dalkon Shield, they can still cause pain, uncertainty, and frustration.    

You can hear that frustration in conversations that women have—among friends, and even strangers, many of them on forums like Reddit. Earlier this year, one Redditor posted about migraines, anxiety, and mood swings that they worried were linked to their device. “I’ve never felt so bad and I’m wondering if [the] IUD potentially cause[d] me all that crap,” they wrote.

Someone else described constant bloating, weight gain, and a loss of libido after inserting a device a few weeks after giving birth. “I hit such a low, I fell into depression and barely want[ed] to look myself in the mirror,” they posted.

Another Redditor wrote about a doctor refusing to help them switch from hormonal birth control to a copper IUD: “he had this very concerned face of like ‘why the hell do you want this,’ ” they wrote. The doctor, they explained, was tired of people suddenly distrusting hormonal birth control.

This is a common dynamic: Doctors are frustrated with patients attributing various maladies to their IUDs (they are right; these days, it is hard to pin many specific complaints on the IUD itself). Patients are frustrated that their doctors won’t take their concerns seriously—or give them concrete answers. They, too, are right.

To understand the current science on modern IUDs, you have to understand how they work: in research terms, the mechanisms of action. In basic terms, hormonal IUDs—the Liletta, Mirena, Kyleena, and Skyla—release a small amount of progestin, whose primary effect is to thicken cervical mucus, effectively putting a wall up in front of the sperm. Copper IUDs—just one is approved in the U.S., the Paragard—release spermicidal copper ions. (Sperm, bless those little guys, aren’t very hardy.)

Beyond the specific effects of hormones and copper, the mere fact of having something foreign in the uterus provides at least some contraception. IUDs of yore, like the Lippes loop and Dalkon Shield, were just plastic—what researchers call “inert devices.” David Hubacher, a senior epidemiologist at FHI 360, told me to think about what happens when you get a splinter in your finger: The body recognizes it’s not supposed to be there and reacts accordingly. To the uterus, the IUD is a sort of splinter; its presence triggers an inflammatory response that, once again, isn’t good for the sperm.

The most desirable outcome of all this is consistent pregnancy prevention—the health consequences of unwanted pregnancy are dire and often deadly. But studies also suggest that a meaningful proportion of users will experience side effects while using an IUD to achieve that end. A portion of these may be desirable—many (though certainly not all) women are thrilled that their hormonal IUD reduces or stops menstrual bleeding. Around 20 percent of women experience no bleeding or spotting by the end of their first year with a 52-milligram hormonal IUD, a rate that goes up over time. (The Mirena is FDA-approved to treat heavy menstrual bleeding.) There are also adverse effects: Some of the most prevalent, when it comes to hormonal devices, are breast pain or tenderness, abdominal pain, acne, and headaches. Copper IUDs are associated with irregular or heavy bleeding, and cramping. (The most robust research we have on IUDs and their side effects, it’s important to note, is funded by the pharma companies who manufacture them.)

But how common are these problems? It’s thorny to definitively say, which is partly because determining causation can be difficult. It’s particularly tricky here because contraception is just harder to study than many other medications. You’re trying to prevent something from happening over the course of several years, and the stakes are incredibly high. “The consequence of a blood pressure medication failing is I stop you on the study and I give you something we know works,” Mitchell Creinin, the researcher in charge of overseeing the Liletta clinical trial, told me. “The consequence of a birth control method failing is you have a life-changing event.” As a result, trials with the devices almost never involve placebos: People enroll in these studies because they want to prevent pregnancy, and you can’t leave that outcome up to the flip of a coin.

One of the things that further complicates decisionmaking around birth control—and the research itself—is that any downsides, even hints thereof, can be politically weaponized. Take, for example, the potential link between hormonal birth control and depression and mood disorders. As Christina Cauterucci has written for Slate, conservative advocacy organizations and influencers—whose rather transparent endgame is to restrict access to contraception—have taken up arms against hormonal birth control, which they say “disrespects women.” In February, Elon Musk tweeted that hormonal birth control “makes you fat, doubles risk of depression & triples risk of suicide,” linking to a six-year-old write-up of a 2016 study from Danish researchers.

The study, which spanned 14 years and was published in JAMA Psychiatry, tracked more than one million women between the ages of 15 and 34, about half of whom were current or recent users of hormonal birth control. Using personal identification numbers and public databases, researchers were able to match the records of contraceptive prescriptions with records that tracked depression diagnoses and antidepressant prescriptions. When they parsed the data, they found that using hormonal birth control “was positively associated with a subsequent use of antidepressants and a diagnosis of depression.” In 2018, the researchers published another study, using the same databases, which tied hormonal contraceptive use to a higher risk of suicide. In a study published earlier this year in the Lancet, researchers used the Danish records to compare different hormonal IUD models and found that lower-dose hormonal IUDs carried a lower risk of depression than their 52-mg counterpart.

At the time, the 2016 study generated all sorts of headlines. “Birth control is turning women into hormonal messes,” the New York Post declared. But the strength of this finding is controversial: As with other treatment-emergent adverse events, it’s hard to pinpoint in which cases hormonal contraceptives like the IUD caused depression, and other studies have mixed—or even opposite—results. The benefit of the Danish study is that it’s really big; the downside is that it’s not very precise. “Often you have to take each study as a piece of the puzzle, and as we go along we get a better picture of what the puzzle is going to look like,” OB-GYN Jennifer Gunter told STAT at the time. She added that it was “really important not to sound alarms based on individual puzzle pieces.”

Slowly—as women have gotten IUDs in, gotten them out, and been desperate for answers along the way—researchers have been attempting to build out that puzzle. A 2022 review of research on the connection between hormonal IUDs and psychiatric symptoms, published in the World Journal of Biological Psychiatry, found 10 studies that pointed to an increased risk for depression among hormonal IUD users, two that found a decreased risk, and two that showed no connection.

Ultimately, the researchers concluded that “despite unreliable data … counselling patients about these risks should be mandatory.” They also pointed out that depression is a “multifactorial disease”—and any effects from the hormonal IUD should be taken as part of a larger equation.

The wishy-washyness of this picture, and the time it has taken to come together, isn’t a conspiracy, nor is it a reason to restrict or shame use of birth control. Jeffrey Jensen, who has done studies looking at the cortisol concentrations in hormonal IUD users’ hair to track stress over time (they found no adverse impact), told me he thought the data was pretty clear: Most women will not experience behavioral side effects from IUDs, but some women will. Clinical studies bear that out. “There’s a subset of the population, and we don’t understand the genetics of these individuals or how to screen for them, but they typically have a worse experience,” said Jensen, who has also led clinical research on the Mirena.

Jensen does think that, in future decades, genetic research could help us predict who will do best with the device. Kavita Nanda, the director of medical research at FHI 360, told me her organization is seeking funding to conduct pharmacogenetic testing during some of their standard contraceptive trials, which could help researchers assess whether genetic variations are associated with differences in, for example, bleeding patterns or contraceptive efficacy. Still, funding is hard to come by. Nanda sent me a PowerPoint slide she likes to share that compares annual global investment in contraceptive R&D—which includes government, industry, and foundation dollars—with how much Americans spend yearly on Halloween costumes for their pets: $117 million to develop better contraceptives; around $700 million to dress dogs up as pumpkins, hot dogs, and bumblebees.

Where does this leave the patient, who is having an IUD whisked—or maybe it feels more like wrenched—into her during a brief appointment?

In an ideal world, providers might sort through each new study about side effects, length of efficacy, and pain management themselves, summing up what they’ve learned, each potential if relatively uncommon downside, before completing an insertion.

In our world, providers are stretched thin, and don’t have time to digest such a complicated, evolving body of research, let alone hold summits with patients to process what it means.

Across gynecology, there’s a larger movement toward person-centered counseling, which requires providers take the time to understand what’s important for a patient in their contraceptive decisionmaking, to fully explain all options on the table, and to support and respect them throughout the process. This means giving patients more time with providers who ask more—and better—questions. It’s hard to predict how someone will do with a contraceptive in the future, but the past can certainly hold clues. For a clinician to help me make an informed decision, they need to understand how my body has reacted to other contraceptives, and what’s important to me going forward. They also need to understand why I’m seeking a contraceptive—is it to prevent pregnancy? To manage heavy menstrual bleeding or another condition? To seek relief from symptoms of perimenopause? They can use that information to lay out which contraceptives might be a good match for my needs, while always leaving the decision in my hands.

In many ways, this is a movement to shift contraceptive counseling from population-level concerns to individual ones. There’s a lot of harm to correct for, including numerous present-day examples of contraceptive coercion, especially among patients of color. “Whether it’s subtle or not, Black women are often encouraged to choose long-acting reversible contraception,” Regina Davis Moss, president of In Our Own Voice: National Black Women’s Reproductive Justice Agenda, told me. In focus groups conducted by In Our Own Voice, Black women shared they were consistently not listened to or trusted by clinicians; they felt they couldn’t rely on their providers for complete information, including about side effects; and they had to do their own research. Women also reported facing provider resistance when they sought to remove an IUD.

As I read through the studies I saved on my computer as part of my research for this article, I often wanted to slam my head into the table. The science we have is quite good, but it’s also complicated and underfunded, and it takes time for it to trickle down to clinicians.

Further, some of those clinicians are worried that spreading negative information about the IUD—even the idea that you might, maybe, have some bad side effects—could both discourage women from seeking out contraceptives and be weaponized by those who want to restrict access more broadly. I understand this fear. But the same fear can translate into a dismissiveness that ultimately makes things worse. If we should indeed be gearing up for a war against contraceptives, women need to understand and feel served by what they’re fighting for. Ultimately, the fact that birth control is imperfect means that we need more choices. Not fewer.

Studies since at least the 1990s have concluded that when people are given information about what an IUD might do to, say, their bleeding patterns, they’re ultimately more satisfied with the device. In other words, when people have the data to make informed choices, they’re happier with those choices. Some researchers might shake their heads at this, pointing to a potential “nocebo” effect—basically the placebo effect in reverse, the idea being that if you tell someone about all the bad side effects that might happen to them, they’ll be more likely to report experiencing those side effects. But this is ultimately a paternalistic concern: If we want birth control for an individual, that individual needs a real seat at the table.

There’s a dangerous tendency to see research as separate from women’s experiences with the IUD—informing it from above, but not integral to it. We know that the modern iterations of the IUD are safe and effective, so we tell women so. We should continue doing that. But we should also tell them what we don’t know, what we’re still studying. We should encourage them to keep asking questions, and to be a part of the process of looking for an answer.

This article was produced in collaboration with ASU Media Enterprise.