New Male Birth Control Device That Reduces Sperm Motility Was Created by German Inventor

The new device is hormone-free and only needs to be used every few months—but you likely can't get your hands on it any time soon, unfortunately.

Birth control pill pack on designed background
Photo: Getty Images

The person who ovulates is often the person who handles contraception. Pills, patches, rings, and IUDs are all highly effective ways to prevent pregnancies, but they all fall on the person who produces eggs.

One German inventor is trying to change that, and she recently picked up some hardware—and headlines—for it. Rebecca Weiss, an industrial design graduate from the University of Munich, invented the COSO, an ultrasound-based, hormone-free "testicle bath" birth control device for men. The device won the James Dyson Award, an honor that "celebrates, encourages, and inspires designers of new problem-solving ideas."

Contraception for men is certainly a problem-solving idea. But back up—testicle bath? Say, what?

According to Weiss' description on the James Dyson Award landing page: "The user puts water into the device up to the indicated mark, which is set together with a doctor according to individual testicle size. Then the water is heated up to operating temperature. COSO is ready for ultrasound treatment. The user spreads his legs and sits down to place the testicles in the device. The ultrasound process continues for a few minutes."

A person only needs to use the COSO every couple of months for it to reduce sperm motility and prevent it from hooking up with and fertilizing an egg after intercourse.

Weiss says she developed the idea after being diagnosed with precursor cervical cancer, a rare side effect of using oral contraception. She had to stop taking birth control.

"When my partner and I were looking for an alternative method, we became aware of the lack of male contraceptives," she writes. "The problem is not unique to me personally. It affects many others as well."

Want a COSO? You'll have to wait. So far, Weiss says the procedure has only been tested on animals. But she received $45,000 for winning the James Dyson Award, and she hopes the newfound notoriety helps her get funding for clinical trials on the COSO.

Would men and other sperm-producing individuals sign on to try it out? Weiss is betting on yes.

"Many men would like to take on more responsibility in matters of contraception," she says. "But the options are limited."

Maybe they won't be for long.

Was this page helpful?
Related Articles