In 1987, Zurich was a hotbed of radical feminism. For three Swiss francs (close to $6 today), left-wing bookstores sold a copy of a pamphlet called “Antisexistische Schrittversuche fuer die Aufloesung Maennlicher Machtstrukturen” (“anti-sexist attempts to dismantle male power structures”), featuring an article about “hodenbaden” sterilization — that is, testicular bathing.
In the absence of reversible long-term contraception for men, and opposing the idea that preventing unwanted pregnancies should be a woman’s responsibility and burden, a group of 11 men called the Zürcher Hodenbader (testicular bathers of Zurich) had devised a system: For 45 minutes daily, they would sit on a custom-designed chair with a heated cup in which they would submerge their testicles in water warmed to about 113° F. To thrive, sperm need a temperature slightly below the rest of the body, which is why testicles hang outside (and tight underwear, saunas, hot tubs, and the like are not great for men trying to conceive). After several weeks of regular testicular bathing, the sperm count would typically drop below the fertility threshold for up to six months.
It was cumbersome, time-consuming, and uncomfortable. Skin burns might occur. But there weren’t any other available options. Four decades later, there still aren’t.
Besides condoms, which have a user failure rate of up to 16%, men can only resort to vasectomies: surgical procedures that cut the vas deferens, the tube that allows sperm to enter semen. But vasectomies can be expensive, and though typically reversible, too definitive a commitment for younger men.
For a long time, it was believed that most men wouldn’t reliably use a birth control method, and even if they did, women wouldn’t trust them, said Heather Vahdat, the executive director of the Male Contraceptive Initiative (MCI), a nonprofit dedicated to funding and advancing male birth control options.
That may well have been the case at some point, she said, but data show attitudes have changed: According to an international survey in 2021 and 2022, 61% of men said they would be open to trying a male contraceptive. In the U.S., only 39% said they would — a percentage that jumped to 49% when the survey was administered again in 2023, after the Supreme Court’s Dobbs decision overturned the federal right to abortion. The same survey showed a majority of female partners outside the U.S. would trust men with birth control. A separate survey conducted in 2023 and published this year found that two-thirds of American women were interested in their partner using birth control, and 75% of them thought their partners would be open to using it.
Supportive male allies are no longer bathing their testicles (the Hodenbaders, and others who took inspiration from the group, ended their experiment when the spread of AIDS made condoms more popular), but they are still trying to do their part — by signing up for clinical trials of experimental male contraceptives.
There is a robust pipeline of male birth control products being tested. Of them, three are relatively close — a few years away — to potential commercialization if the trials are successful. Nestorone/testosterone (NES/T) gel, a hormonal combination that reduces sperm production, has completed Phase 2 studies; YCT-529, a non-hormonal birth control pill for men, is being tested in a Phase 2a study. And ADAM, an implanted gel developed by Contraline that produces a seal that serves as a temporary vasectomy, is currently undergoing a human safety trial in three sites.
Though the results of the NES/T trial haven’t yet been published, the expectation is that the product will be able to continue to Phase 3, said Vahdat. At the same time, researchers have observed a reduction in sperm count in men undergoing the Phase 2a study of YCT-529, according to the company developing it. ADAM has been found effective at eliminating sperm up to at least 24 months after the implant, and since Contraline plans to eventually apply for approval as a device, it could become available in the U.S. on a faster timeline than a medication, for which Food and Drug Administration approval standards are more rigorous.
“Men want this,” said Nadja Mannowetz, the chief science officer and co-founder of YourChoice, the San Francisco-based biopharma startup that is conducting trials for YCT-529. “We are receiving emails from men all over the world asking to participate,” she said. She had initially been worried that recruitment for the Phase 2a trial, taking place in New Zealand, would stall, and has been pleasantly surprised by how many men are lining up to take part.
“We get emails all the time [from men] asking to be connected either to Contraline or to YourChoice folks, or to just be put on some random list to be called when there’s a clinical study,” said Vahdat.
Both companies maintain an online registry where men can sign up to be considered for future trial enrollment. Contraline said it has crossed 20,000 sign-ups for future trials, though only about 200 to 300 will be needed for the next phase of ADAM testing, and 1,000 for the Phase 3 testing of NES/T, which Contraline will be running after licensing it from the Population Council.
Men want birth control to support women, and reclaim agency
With reasons ranging from ideological to practical, the men looking for birth control options come from varied backgrounds. They are reaching out to YourChoice and MCI from the U.S., Canada, Kenya, France, Germany, and more, and interest is rising as reproductive care access for women becomes more challenging — in the United States, as well as in the many countries that used to rely on U.S. funding to provide such care. “After Dobbs, we saw an immediate uptick in men reaching out,” said Vahdat.
Some are being encouraged by their partners. Others are single and uninterested in having children. Some are even experimenting with more modern thermal methods such as the Andro-Switch ring, which raises the testicles back in the inguinal canal, increasing their temperature just enough to lower the sperm count, but are looking for more trustworthy options.
“What is it that brings a man to … want to use male birth control is often his care for his partner,” said Brian Nguyen, a professor of gynecology at the University of Southern California who researches the role of men in contraception. “He’s often seen his partner go through multiple methods of birth control and face various challenges with hormonal side effects, or complications related to the IUD or the implant, and so they want to be able to do something to alleviate the burden off their partner,” said Nguyen, who was in charge of recruiting men for the trial of the NES/T gel.
“I am a huge advocate for women’s rights and it’s always confused me why women have had to take birth control rather than men,” said Gerry Garcia, a carpenter based in Minneapolis who reached out to YourChoice to make himself available for future trials. “Women can only get pregnant basically once a year, by one person, whereas a male can get multiple women pregnant. I think if anybody should be on birth control, it should be males.”
At 41, Garcia says he is past the age when he’d like to have children, and his girlfriend, a mother of one, is not looking for more pregnancies. “I’ve been contemplating getting a vasectomy for a while,” he said, though the cost could be significant even with insurance coverage.
A vasectomy was also the first thought for Edmund Daniel of Ontario, Canada. Without a strong desire to raise children, or a partner who wanted them, he reached an age (his early 50s) when he just didn’t want to take chances. He had a simple, 20-minute outpatient procedure done at the doctor’s office, but when he went back for his one-year follow-up, he found the vasectomy had naturally reversed. “I guess my body took it upon itself to heal and fix it,” he said.
Though a rare occurrence, spontaneous vasectomy reversals happen in an estimated 0.25% of cases, and make the man unsuitable for a repeated procedure: Daniel would need more complex surgery for sterilization, for which the waitlist where he lives is currently six years.
That’s when he started looking for trials for male birth control. “My personal feeling is that that responsibility should be shared” between men and women, he said. This is both from a moral standpoint and from a personal one: “I want to know that I’m kind of doing my own due diligence, that I am not risking anything,” he said.
On the opposite end of the spectrum are men who are too young for kids. “I’m in college right now, and if [my girlfriend] were to get pregnant, that would definitely put a big halt in my life,” said Maddix Elston, a 19-year-old nursing student at Indiana University Southeast in New Albany, Ind. “To be able to have that control of deciding when I’m able to actually financially support a child would be amazing, phenomenal,” he said. He said he doesn’t like “how invasive female birth control can be,” and the “cultural movement to put it on the women.” But Elston is interested in joining a trial out of scientific curiosity, too. “I’ve definitely been very interested in laboratory research, too, so I think getting involved in [a trial] would also allow me to talk to people who are in that career field,” he said.
In France, Ruben Dalu, a headhunter from Les Lilas, a suburb east of Paris, didn’t want kids, but at 28, felt too young for a vasectomy. Still, he wanted to “help take the weight [of contraception] off my partner,” so he tried Andro-Switch. Unfortunately, while it worked for some of his friends, it didn’t reduce his sperm count sufficiently, and the result was an unwanted pregnancy.
He’s now left to contend with a lack of options. “You have no agency,” he said, “it’s a bit scary.” Even if he decided to get a vasectomy, the waitlist in France is long, so he’s reached out to volunteer for trials.
Being in a male birth control trial worked so well for Josias Sop, an IT professional originally from Cameroon and now living in Virginia Beach, Va., that he is looking for another. For about a year and four months in 2023, he was in a trial for the (NES/T) gel, which has been developed by the Population Council, a nonprofit research and development organization focusing on reproductive health. There were some logistical challenges — having to apply it every day and take care not to touch other people, lest the hormones in the gel transfer, or taking special precautions when traveling with the gel — but he was happy with it: He had a reliable, effective birth control that allowed him to share the burden of contraception with his female partner, and gave him agency over his own fertility.
So when the trial was over, he started looking for the next one, and is interested in trying YCT-529 because it comes as a pill. “The gel was a manageable situation, but the pill, for instance, would have been much more efficient in my opinion,” he said. But if a pill weren’t available, “any sort of application, whether daily, weekly, monthly, or something similar would work for me because it’ll give me that control that I’m looking for,” said Sop.
Men are willing to put up with side effects, too
The rubber condom was invented in 1855. The first vasectomy was performed in 1897. How come no other male birth control options have become commercially available in the intervening 130 years?
Some of the reasons are the same as for the imperfect menu of female hormonal birth control methods, which can have significant side effects: The existing options work well enough, and are sufficiently popular, that big drug companies don’t have the financial incentive to develop new, better products. “This isn’t a product area that is supported by the pharmaceutical industry,” said MCI’s Vahdat, adding that a combination of cost-cutting and de-risking measures led pharma to step away from women’s health research and development about 30 years ago.
And yet, some see a double standard at work. In 2016, the Phase 2 trial of an injectable hormonal birth control for men was halted because an independent panel found the product had too many side effects. Women rolled their eyes: The reported side effects, including acne, injection site pain, increased libido, and mood disorders, didn’t seem any more serious than the side effects of hormonal female birth control.
The men STAT spoke with were not concerned about side effects, and were willing to make the trade-off for an option to control their fertility, and step up their contraception. “Considering what women go through for their side effects, you know, I don’t think it’s the end of the world,” said Garcia.
Dalu, too, doesn’t see that side effects or having to stick to a routine would deter him. He had to wear the Andro-Switch 16 hours a day, he said, but that didn’t stop him from complying. “The pill and IUDs already have side effects,” he said, adding that the only true concern would be if a birth control product were significantly harming his mental health.
Having already gone though the NES/T gel trial, Sop knows he can stick with the routine of birth control even if it demands some effort. For a year, he said, he had to apply the gel (typically on his arm), then be sure not to rub it onto other people, which meant no contact for a few hours. “Let’s say your partner wanted to cuddle after application of the gel, that would not be recommended,” he said.
Unfailingly, men mentioned their awareness of the challenges that women may experience because of birth control, and expressed a desire to support them.
“I think that’s easy to think about men as selfish, non-caring or oblivious to this issue, but pregnancy is an issue that affects both partners,” said Nguyen.
STAT’s coverage of health challenges facing men and boys is supported by Rise Together, a donor advised fund sponsored and administered by National Philanthropic Trust and established by Richard Reeves, founding president of the American Institute for Boys and Men; and by the Boston Foundation. Our financial supporters are not involved in any decisions about our journalism.
