Male contraceptive ‘bath’ device invented in Germany, wins Dyson award

Male contraceptives have previously been rejected for several reasons • Coso offers a user-friendly contraceptive that is easy to use without physical intervention, pain or side effects.

Couple touching their hand (photo credit: GETTY IMAGES)
Couple touching their hand
(photo credit: GETTY IMAGES)

Industrial design graduate Rebecca Weiss has created a groundbreaking device – a testicular ultrasonic "bath" that could function as a male method of contraception.

The invention could be the much-awaited answer for long-term, safe, male-based family planning. The current options for males are condoms – which are beneficial to also prevent sexually transmitted diseases but are uncomfortable for most partners as continuous pregnancy prevention – and vasectomies, arguably the safest method of birth control, but irreversible.

Weiss first investigated the notion of male birth control after receiving worrying results from a gynecological exam that revealed precursor cancer cells on her cervix, the young inventor said, according to the Dyson Awards website. As oral contraceptives carry female hormones of estrogen and progesterone, they are inadvisable in the context of suspicious cancerous cells, so Weiss searched for alternatives.

Coso, her mug-sized bath-like invention, is a small sleek bowl that uses ultrasound waves to temporarily disrupt sperm regeneration, leaving the user free to practice birth-controlled sex two weeks after using the device.

The user fills the cup with warm water and place his testicles inside, while the ultrasound waves target the sperm cells. The mechanism has been successful in animal tests, but has not yet been applied on humans.

 Different kinds of birth control pills. (credit: Ceridwen/Wikimedia Commons) Different kinds of birth control pills. (credit: Ceridwen/Wikimedia Commons)

The effect wears off up to six months later, meaning it does not have to be an irreversible solution like “tying the tubes.”

The young designer studied male fertility as part of her thesis at the Technical University in Munich. She hopes her innovation will receive the financial and academic support necessary to reach clinical trials and medical practice.

"Coso… offers a user-friendly contraceptive approach that is easy to use without any kind of physical intervention, pain or previously known side effects," said Weiss. “New technologies only work if they are accepted by users and society.”

Male contraceptives have previously been rejected for several reasons. A pill was abandoned when it reportedly caused headaches – despite the fact that hormone-filled female contraceptive pills can cause similar headaches as well as depression, mood swings, breast swelling, blood clotting issues and even stroke. 

Another reason contraception is still in the female arena is due to the simple fact that many still perceive pregnancy as “the girl’s problem.”

But long-term couples often want to share the responsibility. "The problem is not unique to me personally," said Weiss. "It affects many others as well. This is also evident in the current growing public discussion about the lack of contraceptive alternatives."

The innovation has won the international James Dyson Award that celebrates design and engineering. Whether the ingenious, attractive gadget could also become a breakthrough in contraception remains to be seen.