Mice Sperm Pave the Way for Male Birth Control Pill

New research out of Osaka suggests a male birth control pill may be closer than we thought—no scary needles required.

by Lauren Oyler
Oct 2 2015, 8:35pm

Photo by Studio Firma via Stocksy

A new study published in Science yesterday suggested that researchers at Osaka University's Research Institute for Microbial Diseases may have discovered two drugs that would work as a future male birth control pill. This is great news for women who don't like birth control's current paltry options and for men who want to share the burden of contraception without the scary-seeming procedure required of the current frontrunner in the race to stop sperm, Vasalgel.

How it would work: When tested in mice, the two drugs, which are normally given to organ transplant patients to suppress the immune system's rejection of a new organ, made spermies' tails too stiff to engage in "hyperactivation," which is when they move really, really fast and with enough force to break through the membrane that surrounds an egg. After one week off the immunosuppressants, the mice regained their fertility.

In the wasteland of male contraception, this is really promising, says Aaron Hamlin, the co-founder and executive director of the Male Contraceptive Initiative, an organization that promotes awareness and raises funds for male contraception research. "It's really difficult to miss the big gap around male contraceptives," Hamlin says. "Withdrawal, condoms, vasectomies—that's it."

Read More: Pulling Out Is as Effective as Using Condoms

While feminists and disgruntled condom users rejoiced at this year's news that male birth control was on the three-to-four-year horizon, fewer were enthused about the form it would take: Some headlines hailed the drug as "the male pill," but Vasalgel is actually a polymer that requires a one-time injection into the vas deferens. Although it will not require a shot to the testicles, as some horrified men assumed, it's still kind of invasive. According to Hamlin, at least for awhile, Vasalgel would be more of an alternative to vasectomy—which about half a million good men of America get each year, he says—than an easy lifestyle change, like a pill would be. It will be many years after Vasalgel is released onto the market before researchers will know if the drug is truly reversible, and this Japanese study, though early, is already promising on that front.

"Many guys' reluctance about vasectomy isn't so much the invasiveness of it," Hamlin says. "It's the permanence of it. They want something that works but if you want to have kids later, you can still reverse." By contrast, he says, "It seems likely that [the immunosuppressants from the Japanese study] will be a pill."

It's really difficult to miss the big gap around male contraceptives.

When I ask Hamlin if he thinks men are receptive to contraception generally, he says yes, though he adds that "there may be a bit of sampling bias here, because the people we [the Male Contraception Initiative] talk to are crazy about being able to get a male contraceptive." Indeed, a rotating feature on the Male Contraception Initiative website called "What's Your Reason?" highlights quotes from supporters on why they want better contraception for men. These include "I cant [sic] climax with a condom" and "It's absolutely terrible to have no other option as a male. I'm just 17, and thinking that I'll have to spend 50 years using the condom with no other possibility? That would be awful. I want something new!"

In 2005, a nine-country study of more than 9000 men aged 18-50 suggested that just over 50% of men would consider taking a new method of male birth control. Hamlin is confident that that acceptance will rise as non-hormonal methods—like Vasalgel and this new hypothetical pill—become more of a reality. "What's interesting is that [the 2005 study] is looking at hormonal methods," he tells me. "You can imagine how much that number would go up if people were surveyed about non-hormonal methods."

Indeed, women have become increasingly vocal about their dissatisfaction with available birth control methods in the last few years, with hormones being a main source of resentment. Hormones fuck many people up, and while the ParaGard non-hormonal IUD is a good solution to this problem, it can cause heavier, more painful periods.

In this new version of the contraceptively equal future, men will be free of the bloating and lowered sex drives that are often side effects of the female pill, but guys would still have the not-ideal situation of having to remember to take a pill everyday. However, another advantage to a non-hormonal pill is that it could be better at preventing pregnancy despite imperfect use. As anyone who has panicked upon realizing that she forgot her pill knows, the female pill has a less than one percent pregnancy rate when taken at the same time everyday, but that rate goes up when you miss a dose. Men may not have to deal with a daily schedule quite so punctual. "This pill may possibly have the ability to be robust to missing [a dose]," says Hamlin. "It may be possible that a pill for men will be more robust to human error [than the pill for women]."

It's absolutely terrible to have no other option as a male. I want something new!

Ultimately, when I asked Hamlin if he was optimistic about the Osaka research eventually bringing us a real, live, male birth control pill, he was cautiously so. "Contraception development, like any kind of drug development, is very challenging," he says. "They're in the early stages. But it's always a good idea to have a lot of male contraception options in development. It's good to have as many options as possible."