A new male contraceptive method that can replace condoms or vasectomies has been developed. An American corporation has created a male contraceptive device that is effective for two years with a single injection. The burden of contraception can now safely be shared by men.
◇Surgery takes 10 minutes, no significant side effects detected
The British Guardian reported on the 24th (local time) that “the American corporation Contralin has passed clinical phase I trials for the contraceptive device Adam, which prevents sperm movement.”
Adam works by injecting a water-soluble hydrogel into the vas deferens to block the movement of sperm. The hydrogel contains a lot of water, similar to jelly, making it a soft substance.
Sperm is produced in the testes, travels through the vas deferens and the urethra, and is expelled from the body. The sperm blocked by Adam loses its way and is absorbed by the body. Men will ejaculate only the semen lacking sperm.
In the clinical trial, 25 males received local anesthesia, and a water-soluble hydrogel was injected into the vas deferens for about 10 minutes. As a result, no sperm was detected in the semen from 12 to 24 months. The hydrogel was absorbed by the body over time, and no significant side effects were observed.
The corporation plans to conduct clinical phase II trials this fall with 30 to 50 participants. The company noted, “Three-quarters of couples worldwide rely on women for contraception,” adding that “Adam could present an attractive contraceptive option for men.”
◇Research on male contraceptive pills is also ongoing
Research results on male contraceptive pills are being reported one after another. A team led by Dr. Yuki Kaneda at Osaka University in Japan stated in March that “the protein created by the gene 'Tex38' affects the morphology of sperm.” It implies that controlling this protein could induce male infertility.
The research team confirmed in experiments with male mice that the protein made from the Tex38 gene stimulates other proteins to remove unnecessary cytoplasm, allowing sperm to acquire the proper shape. Mice lacking Tex38 failed to remove cytoplasm properly, resulting in malformed sperm with bent heads. Malformed sperm could not fertilize eggs, leading to infertility. The research team stated, “This provides an important clue for the development of male contraceptives.”
There are also contraceptive pills that are effective for two hours after a single dose. A research team led by Professor Jochen Buck at Weill Cornell Medicine stated that “using a drug can eliminate sperm motility when necessary,” with the study published in the international journal Nature Communications in February 2023. This method suppresses the proteins that determine the ability of sperm to fertilize eggs.
The research team administered the protein-inhibiting drug 'TDI-11851' to male mice. The contraceptive effect was 100% after two hours and 91% after three hours. After 24 hours of the mice taking the drug, the contraceptive effect dropped to 0%. This implies that contraception can only be done briefly when desired. Professor Buck stated, “Researching effectiveness and side effects when used on humans will help develop a safer male contraceptive.”
◇Contraceptive device market projected to reach 36 trillion won by 2036
Oral contraceptive pills were first developed in the United States in 1956 by biochemist Gregory Pincus. The U.S. Food and Drug Administration (FDA) approved the sale of oral contraceptive pills in 1960, allowing women to choose pregnancy and childbirth for themselves. The first oral contraceptive pills were introduced in South Korea in 1968.
The development of male contraceptives began in China in the 1970s. It involved extracting toxic substances from cotton seeds, but was halted due to severe side effects. In South Korea, with the family planning policy of ‘Give birth to only two and raise them well,’ vasectomies gained attention during the 1970s and 1980s. The government offered priority for apartment applications in Banpo, Seoul, for those who underwent vasectomies. There were also cases where reservists were exempted from remaining training after undergoing vasectomies.
Yet, men were reluctant to use contraception. Now, the situation has changed. In several public opinion surveys, over half of both men and women responded that they would take or want their partners to take male contraceptive pills. The market is maturing. According to the market research firm Research Nester, the global contraceptive device market is expected to grow from $12.2 billion (18 trillion won) in 2023 to $25.1 billion (36 trillion won) by 2036. It is anticipated that male contraceptives or devices will capture a significant portion of the market once commercialized.
References
PNAS (2025), DOI : https://www.pnas.org/doi/10.1073/pnas.2417943122
Nature Communications (2023), DOI : https://doi.org/10.1038/s41467-023-36119-6