Between sips of tea in a Shoreline coffee shop, Michael Sworen gently bobbed his seven-month-old daughter Amelia on his knee. It’s fitting he brought his infant daughter along for the interview—she’s exactly what we were talking about avoiding.

Sworen and his wife are currently enrolled in a clinical study at the University of Washington School of Medicine testing the first ever gel-based male contraceptive. He’s been using the experimental gel, a mix of testosterone and a sperm-suppressing hormone called nesterone, for just over three months now and his sperm count has dropped to nearly zero.

“I always thought it would be fun to be part of a clinical trial, it’s something no one else has done yet,” Sworen said. “There are no good birth control options for men, but women have the shot, the IUD, the pill, like half of which made her crazy,” Sworen said, referring to his wife, “a few others killed her sex drive.”

Child rearing—and by extension birth control—has long been unfairly deemed a woman’s responsibility, so sexism was baked into the research and development of contraceptives. Not only was the testing of these products highly problematic, but they also reinforced the assumption that sexual health was solely a female problem.

Male birth control is not a new idea, but the medical interest and research funding have only materialized in the last few decades as attitudes about the shared role of parenting slowly move toward a more equal picture of domestic bliss. Despite birth control’s sexist origins, there are some very real reasons contraceptive options for women were prioritized.

“You have to remember that pregnancy is still a life-threatening condition for women, so the social imperative, as well as the biological imperative for women to have contraceptives, is completely different than it is for men,” said Dr. Stephanie Page, a professor at University of Washington’s School of Medicine and one of the lead researchers for this trial. “So appropriately, that’s where the science was focused initially. At least I would say appropriately.”

If a guy gets a woman pregnant by accident, the consequences for him are social and maybe economic. If a woman gets pregnant, she could die. That may sound hyperbolic, but America has the highest maternal mortality rate of any developed country. Not only that, it’s rising while essentially every other country’s drops. Maternal mortality was about 23 times higher in the U.S. back when the Comstock Act outlawed all forms of birth control. Mortality rates for women of color are even higher, with black women today dying at more than three times the rate of white women.

One of the obstacles for male birth control was that scientists had to figure out just how infertile men had to become for the method to be effective. With women, the math is pretty easy. There is one egg every month, so all scientists had to do was stop that egg. But every time a guy ejaculates, he produces, on average, anywhere from 38 to 500 million sperm. How many of those do you have to get rid of before a man can safely claim he won’t get someone pregnant? After all, it only takes one sperm cell to make a baby.

It took decades to fully answer this question. The sperm count has to dip really, really low. This clinical study, which is led by UW and UCLA, is shooting for a concentration of less than 1 million sperm cells per milliliter of semen that they say will be 99 percent effective at avoiding pregnancy, about the same as other leading contraceptives for women. It’s taken 20 weeks of use for the earliest trial participants to get their sperm counts down below that threshold.

Sworen and his wife, along with several other couples in Seattle and LA, have finally reached the part of the trial where the only form of birth control they’re using is the gel. Their condoms are collecting dust in their dresser drawers while they take this scientific leap of faith.

“It’s not weird, well I guess it is weird, but being infertile is kind of a sobering feeling,” Nathan Yoder, a Tacoma bank teller and participant in the trial said. “Not depression or anything, but just weird to think about I guess. Like I couldn’t have kids right now if I tried.”

There are only 266 men on earth who can relate to what Sworen and Yoder are going through. There’s only been one other study where male birth control was tested in couples. A 2016 clinical trial used an injectable cocktail of testosterone and progestin, a class of chemical hormones that interrupt sperm and egg production, to prevent pregnancy in couples. But the trial was ended early after men started experiencing some pretty serious side effects, leading to a lot of online eye-rolling from women who have experienced terrible symptoms for years.

This study did raise some serious red flags for the scientific review board. One man attempted suicide, at least two developed severe depression that may have derived from the hormones, and a significant number of participants experienced mood swings. Although she can’t say for sure, Page thinks these side effects may have something to do with the fact that these injections were administered once every eight weeks.

“The gel has the potential advantage of being self-applied and it produces smoother hormone levels,” Page said. “When you give injections, they’re very good and they can be very effective for some people, but they do produce a little bit more of a peak and a trough. So that might have been one of the reasons they saw some of the concerning side effects.”

Absorbing a small dose of hormones every day will likely keep men at a much more consistent level instead of a deluge of testosterone every two months that could induce mood swings. Neither of the participants I talked to had experienced any side effects after three months of using the gel, but, as they understand it, there are still risks, especially the biggest side effect of all: getting pregnant.

Researchers were very upfront about the possibility of an unplanned pregnancy and have very specific criteria to recruit couples that are prepared for that outcome.

“We have two kids now and always assumed we’d have three, so we definitely discussed it,” Yoder said. “The timing's not right, but if it happened it would be okay. We would have the kid and love the kid and we’d be fine.”

In the 2016 trial, four out of 266 couples got pregnant, which is about 1.5 percent. It is essentially inevitable that some couples in the study will become pregnant, but Page thinks that limiting that to only “one or two pregnancies” would be a success. Couples have complete control over their decision whether or not to go forward with the pregnancy and trial physicians are available throughout the process.

“We’ve made sure there would be no side effects pregnancy-wise if I was on the medication with weaker sperm or something like that,” Yoder said. “The physicians assured us that wouldn’t be the case.”

Perhaps the biggest hurdle scientists and marketers will face once this gel hits the shelves is convincing men that it’s not permanent. Women had the same fears when the first forms of hormonal birth control became available; you are, after all, becoming voluntary sterile.

“The real scary part is going to come once the trial is over and we’re kind of on the cool down period,” Sworen said. “Like is [my sperm count] going to go back up like it’s supposed to? Is my body going to know what to do and start producing again or what’s going to happen?”

The short answer is yes, this is completely reversible, it just takes time. Even the most productive testicles can’t replenish hundreds of millions of sperm overnight because it takes about 72 days to produce sperm cells. This is the second phase of the clinical trial. In phase one, they tested the gel with only men to make sure it actually suppressed sperm production and then rebounded. They never would have reached phase two if it didn’t check off both those boxes. But even with that evidence, participants can’t help but wonder.

“It’s always in the back of your head like, ‘what if it’s permanent and when I’m done with the study the count doesn’t come back?’” Yoder said. “I’m not too worried about it, but it’s something that’s in the back of your mind.”

Both participants said incorporating the gel into their daily schedule has been easy. As Yoder puts it, “if you can apply deodorant, you can rub a gel on your shoulder.” He chooses to apply it every morning after a shower and then throws on a business shirt so his wife and kids don’t come in contact with the testosterone-rich gel. Sworen chooses to apply it every night before going to bed after returning from his job as a chef in Ballard.

Right now, only couples in Seattle and LA are actively using the gel, but researchers are recruiting worldwide. This multisite study will have separate hubs in Kansas, England, Italy, Chile, Kenya, and Sweden to access a diverse pool of participants. Researchers want to make sure they develop a product that works for everyone. But even if they create the perfect male contraceptive, the final hurdle is actually getting men to use it.

The wide use of male birth control could allow women who suffer severe side effects from contraceptives to simply stop using them. It’s just a matter of convincing men they’re reversible, simple, and safe.

“I think we’re selling men short if we say men won’t be willing to tolerate it,” Page said. "So that’s why the goal is to create a menu of options for men. Maybe for two years they use the gel and then their partner uses contraception; these are not lifelong things. Many women use all sorts of contraceptives during their lifetime, so there’s no reason to think that men wouldn’t accept that they don’t have any choices.”

FDA-approved male birth control is still at the very least a decade away, but this gel represents the best bet we have right now for a commercially viable contraceptive. There is a real demand for male birth control out there. Global surveys show attitudes toward male contraceptives vary by region and age, but they average out to over half of respondents saying they would try birth control if one existed. Australians were even more enthusiastic, with 75 percent of new fathers surveyed said they would try a male method.

Yoder believes this is good for more committed relationships and that it makes a lot of sense. They already have built up that trust with their partner and the man may want to alleviate the burden of birth control. Both Yoder and Sworen said their wives had experienced unpleasant side effects, so this allows them to shoulder that responsibility for a while.

“I’m not having any side effects and it’s just as effective as hers,” Yoder said. “If I can help out my wife so that she doesn’t have to hurt, then why not?”

If that’s too charitable an explanation for you, then consider a more selfish motivation. Men want to control their fertility. They may not have as much at risk physically, but men also want to avoid unplanned pregnancies and this may give them the peace of mind that relying on condoms or a partner’s birth control wouldn’t.

If you’re a guy and you’ve read this far, maybe consider signing up. There’s a whole list of criteria you have to meet—you must be healthy, must be in a committed relationship, must live near one of the clinical sites—but, if you qualify, you could be part of medical history.

“They said it’ll take a while, but maybe in 10 or 20 years this could be the new norm, like over the counter birth control gel for guys right next to the condoms,” Yoder said. “It’s kind of cool to know that maybe, my wife and I will be 50 by then, but we’ll be like, ‘we were in the clinical trials for that.’”