Kara Meredith remembers the moment she realized that the problem could be birth control: She was at Subway, paying for a chicken club. The guy at the register told her to have a great day. Then she started crying.

“I was like, ‘Thank you, that is the nicest thing anyone has ever said to me,’ ” said Meredith, a 30-year-old graduate student based in Memphis. “And then I was like, ‘Woah. Kara, what is happening to you?’ ”

Meredith’s emotions had been off for a while. She’d feel fine, then spontaneously burst into tears — at work, in the car, in her parents’ living room. Eventually she told her parents and her boyfriend to, please, just ignore it. She wondered if she might be depressed, and thought about seeing a therapist. Her mom chalked it up to stress. But then Meredith started wondering about her birth control.

A few weeks ago, she had switched to a new pill.

Hormonal birth control affects everybody differently. Many people will happily settle into the first method they try, noting no changes besides their new sperm-rebuffing superpower. For others, though, birth control is a journey.

(Lily illustration)
(Lily illustration)

I spoke to 15 women — and heard from another 70 through an online form — who have explored multiple types of hormonal birth control: IUDs, Depo-Provera (a quarterly shot), Nexplanon (an arm implant), NuvaRing (a plastic ring inside the vagina), and a wide assortment of the dozens of different kinds of pills on the market. They described birth control as “pure trial and error” or an “endless guessing game:” starting on one option, waiting for a few weeks, then trying to figure out how they feel.

You can’t exactly turn to research. While millions of women now regularly use some form of hormonal birth control — approximately 28 percent of women between the ages of 15 and 44 — there are staggeringly few conclusive studies on its side effects. Doctors still struggle to pinpoint exactly how any particular type will affect us, says Sarah Hill, author of “This is Your Brain on Birth Control.”

“It’s critical that the next stage of this research takes into account the specific type of pill that a woman is on,”Hill said.

Hormonal birth control works by releasing artificial versions of estrogen and progesterone — or sometimes just progesterone — tricking our brains into thinking we’re at a point in our cycle when our ovaries don’t need to release an egg.“ Different kinds of birth control have different progestins [a synthetic form of progesterone], and the ratio of progestins relative to estrogen also differs,” Hill said. “All that is going to affect women’s behavior in different ways."

The result can be hours of furious Google searching and conversations with friends, exchanging stories of various side effects. The hardest part of the birth control journey, many women said, is trusting yourself: believing that you really do feel how you think you feel — and that birth control might have something to do with it. Then you need to have the money, insurance and access to medical care necessary to make the switch.

“The [side effects] can sometimes be very intangible and hard to describe. Like ‘I feel crummy:’ how do you quantify that?” said Margaret Murdock, a 23-year-old graduate student based in New York, who tried three different kinds of birth control before she found one she liked. “You need to be able to know yourself and advocate for yourself,” she said. But that’s not easy, especially when there is so little definitive research.

Pulling out of the Subway parking lot, Meredith wasn’t entirely sure that birth control was what was behind her emotional shift — but she knew she had to make some kind of change. She called her nurse practitioner.

“I cannot live like this,” Meredith said, crying into the phone.

She switched pills, choosing one with a different ratio of estrogen to progesterone. Within a few weeks, she said, she felt back to normal.

When they first went on birth control, many women I interviewed were far more aware of certain side effects than others. Weight gain, for one, was on everybody’s mind.

“My mom and friends all told me that they’d gained weight on birth control,” said Katie Rosenfeld, a 27-year-old graduate student in New York. “And sure enough, I put on 10 pounds.” She never wondered why her body had changed so fast: She knew immediately to blame the pill.

Other physical side effects were also relatively easy to peg to birth control: hair loss, changes in skin, changes in bleeding patterns. With physical symptoms, several women said, they could point their doctors — and themselves — to something tangible that was not there before. For quite a few women, physical side effects were positive: many chose to stay on birth control, even when they weren’t sexually active, because it cleared up their skin.

With less visible symptoms, women said, it was harder. For over a year after getting the Nexplanon implant, Maggie Germano, 32, had a hard time having sex. Almost every time she did, she said, it was extremely painful. Germano, a financial coach based in Washington, D.C., never thought her birth control could have anything to do with it, until a few more physically obvious symptoms — weight gain, acne — prompted her to have her implant taken out. She switched back to the pill. Soon after that, she said, sex stopped hurting.

“I was just putting up with it, which is crazy,” she said. “It took way too long for me to do something about it.”

Germano had always assumed there must be some other reason sex became painful: maybe it was the issue she’d been having with her thyroid, or a side effect of her anti-depressants. After she got her implant removed, she listened to an episode of “Bodies,” a podcast about medical mysteries: It was all about how birth control can lead to painful sex.

“Listening to that made me really angry,” Germano said. She wanted to know why no one ever told her about that potential side effect. “Why are so many of us putting up with this crap?” (Three other women told me they experienced something similar.)

Many women put up with a shift in mood for similar reasons: They assumed something else, besides birth control, must be causing it. It was the side effect that cropped up most in interviews and form responses. Thirty-three women said that their birth control negatively impacted their mood, either making them depressed or prone to unpredictable emotions. Other research has shown the same outcome. Some percentage of people — experts can’t say exactly how many, according to Hill — will feel differently once they start taking certain types of hormonal birth control.

“We know that everything that only has progesterone will affect mood more than something with an estrogen component,” said Christina Theriault, a nurse practitioner in Fort Kent, Maine. “I’ll say to patients, if you are sensitive to hormones or have an existing mood disorder, this one will be a better option.” But it’s not an exact science, Theriault said. “You have to acknowledge that everyone reacts differently — and at different stages of their life, too.”

For people prone to severe PMS, Hill said, the changes can be positive. Birth control gives your body the “same hormonal message” every day, she said, so your body is less likely to “freak out” from the more drastic hormonal shifts that can occur in the natural cycle. But for others, hormonal birth control can be a depressant, said Theriault, particularly forms with fewer progestins.

When your mood changes, birth control isn’t the first place your mind goes, women said. While depression and anxiety are typically listed as potential side effects, some women said no one had ever told them that. Nicole Coletti, now 26, got her first birth control prescription at her college health care center when she was 18. She remembers the nurse discussing the possibility of breakouts and weight gain. Another doctor told her the pill could help with depression and anxiety.

“I took that as gospel,” Coletti said.

When she started experiencing mood swings, Coletti thought it might be her own mental illness acting up in a new way. At the time, she had been on and off of anti-anxiety medication.

“It took me years to understand what changes to my body are caused by hormones. For a long time, especially in college, I’d ask myself, ‘Why am I like this? Why is this happening to me?’ ” (Coletti realized that her pill had been the problem when she switched to Nexplanon for other reasons, and her mood stabilized.)

Friends or family members often had to suggest that birth control could be the problem before women came around to that idea themselves. Savannah Bland was in college when she started feeling much more emotional than usual. She cried a lot, and became angry easily. Eventually her boyfriend pointed out that she seemed different, and asked whether it might have something to do with her birth control. His mom, he said, had gone through something similar.

“I needed someone to tell me it was okay to go to the doctor,” said Bland, now a food technologist on a cattle ranch in central Texas. “It took a lot of soul-searching for me to realize that I wasn’t crazy for feeling the way I was feeling. I just needed to trust my own body.”

She switched from the pill to NuvaRing.

Audri Wennekers, 18, also noticed her mood change because of birth control — but she decided she could manage the emotional shift. Before she went on birth control, her periods were debilitating. She’d regularly have shooting pain in her stomach, across her hips and down her legs.

“You couldn’t really sleep with it, and eating sucked. Sitting was uncomfortable,” said Wennekers, who lives in Alberta, Canada. “So you’d just watch a movie and cry.”

When she went on the pill, she said, all that went away. But she started to isolate herself — crying a lot, spending more time alone in her room. Her parents pulled her aside at Thanksgiving to tell her they thought she might be depressed — and, just based on the timing, they suspected it might be her birth control. Her doctor agreed, but Wennekers stayed on the pill anyway, choosing to start taking low-dose anti-depressants.

“I decided I’d rather deal with depression than deal with my period. To me, that seemed so much easier than a week of cramps and a week of recovering from cramps,” Wennekers said.

Laura Ginsberg was hit hard with a side effect that is particularly tough to recognize: She didn’t want to have sex. Sex wasn’t painful, or bad in any particular kind of way. She just wasn’t that into it.

It’s a common side effect that’s rarely talked about, Hill said. Many forms of birth control can deplete a woman’s testosterone levels, which, for some, will affect sex drive. (Seven women besides Ginsberg wrote in the survey that birth control depressed their libido.)

For Ginsberg, it happened gradually. Now 31, she went on the pill when she was 18. For five years, everything was fine. But when she started losing interest in sex with her long-term partner, whom she married at age 25, she blamed herself. She would fixate on things she’d read online or in magazines, about couples having “amazing wild sex” every night. She wanted to know why she couldn’t make herself want that.

“It is so hard because it’s not like you’re operating in a vacuum,” Ginsberg said. “You’re thinking, ‘Okay, I’m getting older, I have a lot of stress at work, I’ve been in this relationship for a while and maybe the spark is just going away.' ” Like many women, Ginsberg didn’t know that her reaction to a specific type of birth control could change: Her sex life had been fine when she went on this particular pill, she thought, so she assumed birth control couldn’t have anything to do with it.

Ginsberg went off the pill when she and her husband started trying for a baby. She was stunned by how she felt.

“It all came rushing back,” she said. “I was like, oh, this is what it means to be a normal, healthy woman.” By the time she went off birth control, she’d mostly reconciled herself to a future without pleasure or desire.

It was a relief, she said, to realize she still had many years of good sex ahead.

So, hormonal birth control has some problems. That doesn’t mean people swear off it completely. Of the 85 women who filled out the survey, only 23 stopped taking hormones altogether: Of those 23, seven chose the sans-hormone Paragard IUD, while the rest opted for condoms or natural family planning methods — or decided that they were ready to have kids. Those strategies, obviously, are not without risk. Two women got pregnant when they didn’t want to be after going off birth control. Both decided to have an abortion.

But roughly the same number of women — 27, between the online form and interviews — weren’t ready to give up on hormonal birth control. When they were ready to part with a particular side effect, they just tried a different hormonal cocktail: exploring Nexplanon, an IUD or a new kind of pill. If that mixture didn’t work, they tried again, as many times as it took to get it right.

Murdock feels lucky to have so many birth control options: She’s acutely aware that, not too long ago, she would have had far fewer. She just wishes the whole thing felt less like a science experiment. When she told her doctor about her side effects — joint pain, intense cramping, perpetual sadness — Murdock remembers, the doctor shrugged.

“I told her it wasn’t working for me and she was like, ‘I don’t really know why that is. There is so much we don’t know about the long-term and short-term effects.’”

Telling her nurse practitioner about her emotional visit to Subway, Meredith felt the same way. “The NP was like, ‘Yeah, I don’t know. I don’t know why this did that to you, but we should never put you on that type again.’ ”

Meredith couldn’t believe how “inexact” it all was. She’s glad that she was sure enough of herself to say something. She was able to go beyond a cursory Google search for “crying birth control,” and dig deep into Reddit archives, where she found other people with stories just like hers.

The trial-and-error approach to birth control is a relatively privileged one, said Rachel Fey, the director of public policy for Power to Decide, a nonprofit dedicated to preventing unintended pregnancy. Many clinics that rely on government funding (and serve primarily low-income women) can’t offer the full range of birth control options, said Fey. That is especially true, she said, since President Trump implemented the “gag rule,” prohibiting all Title X funding recipients from providing abortions or abortion referrals, prompting many clinics to turn down federal funding altogether.

Even if there are a wide array of options available, Fey added, women struggling to pay their bills likely won’t have the time or resources necessary to dabble in a lot of different methods. “Every time something isn’t working for you, you have to go back to your doctor. Imagine being someone who has to think about every dollar they put in their car for gas, every extra hour they have to take off work, every extra minute they have to have their kid in child care,” said Fey.

The danger in worrying too much about side effects is that women might choose to go off birth control entirely: It’s important to remember, Fey said, that nearly half of all pregnancies in the United States are unintentional. (The most recent comprehensive statistics on unintended pregnancies are from 2011.)

Even when women do manage to nail down the type of birth control that works best for them, they still might not be able to access it. Murdock had to stop taking a pill she loved when she went off her parents’ insurance, and joined a plan through her employer. Her original pill wasn’t covered.

“I was paying tuition, paying my loans. I didn’t have the extra money to pay for this medication every month,” Murdock said. “Knowing that there was a solution out there that I didn’t have access to for such a pedantic reason was very frustrating.”

Theriault, the nurse practitioner in Maine, sees this kind of thing all the time. Low-income patients come in wanting an IUD, but don’t have insurance and can’t afford to pay the $1,000 price tag all at once. Some patients know pills don’t work well for them, Theriault said, but that’s the only kind of birth control they can afford.

Hopefully soon there will be better research, allowing doctors to more precisely predict which type of birth control to prescribe to which patient. But in the absence of that research, women should at least learn the language of birth control, said Coletti, who knew nothing about potential emotional side effects when she started on the pill in college.

“I didn’t have the language to ask some of the questions I really wanted to ask,” Coletti said. “I didn’t know the mechanics of hormonal birth control. I didn’t understand the difference between the pills. So I didn’t have the confidence to advocate for myself.”

When she realized that her mood swings could be a side effect of birth control, Coletti said, she felt ashamed. All her friends could “get things to work right,” she said. Why couldn’t she?

Coletti has tried five different types of birth control in eight years, searching for the precise hormonal combination that feels just right.

She’s still looking.

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