First Male IUD (STEOM) in Development, Expected by 2033
A team of researchers at the CHU de Lille in France has developed the world’s first male contraceptive device comparable to an intrauterine device (IUD). Named STEOM — often referred to as a “sperilet” or male IUD — the mechanical, non-hormonal device is designed to be fully reversible and is expected to reach the market by 2033 at the earliest, pending regulatory approval.
A New Option in Male Contraception
The STEOM device represents a significant step forward in expanding contraceptive choices for men. Currently, male contraceptive options in Belgium and France are limited to condoms, vasectomy, and the thermal method (heated underwear), which remains marginal. Female contraceptive options, by contrast, include the pill, hormonal and copper IUDs, implants, patches, rings, injections, and diaphragms.
According to RTBF, the device is “completely mechanical — there are really no hormones and no medications,” explained Dominique Prasivoravong, CEO of the STEOM startup and one of the four researchers behind the innovation.
How It Works
The STEOM device measures approximately one centimeter and is placed on the vas deferens — the ducts that transport sperm from the testicles. By mechanically blocking these ducts, the device prevents sperm from entering the semen, effectively acting as a reversible alternative to vasectomy.
“We like to say it’s a faucet,” Jessica Schiro, technical expert at the CIC-IT research center, told France 3 Régions. “It’s really the counterpart of the female IUD — the mode of operation is the same.”
The insertion procedure takes approximately 15 minutes under local anesthesia, requiring a single one-centimeter incision in the scrotum. No stitches or bandages are needed, and patients can resume normal activities immediately.
Reversibility: A Key Advantage
Unlike vasectomy — which involves cutting the vas deferens and is considered permanent — the STEOM device is designed to be fully reversible. Removing the device restores fertility, making it an attractive option for men who want contraception without a permanent commitment.
“The big advantage is that it’s reversible,” Prasivoravong told RTBF. “By removing the device, you regain your fertility.”
The device is expected to be effective for at least three years, the initial regulatory approval period, though researchers believe efficacy could extend longer.
Development Timeline and Belgian Connection
After four years of research and a patent secured in 2025, the STEOM device is now entering its next phase. Preclinical trials on dogs are imminent in partnership with the University of Liège (ULiège) in Belgium, as reported by La DH.
If these trials are successful, the first human implantation is expected around 2030 as part of a clinical study. Commercial availability is projected no earlier than 2033, pending approval under European medical device regulations.
Addressing the Contraceptive Burden
The development of STEOM is driven in part by a desire to share the contraceptive burden, which currently falls overwhelmingly on women. A study by the Belgian Institute for the Equality of Women and Men found that women still bear primary responsibility for contraception.
“The idea is to also offer men contraceptive solutions to lighten the contraceptive burden that is currently carried essentially by women,” Schiro told RTBF. She noted that many women are moving away from hormonal methods, creating demand for shared responsibility.
Dr. Julie Prasivoravong, andrologist at CHU de Lille and CH de Lens, told Le Point (via La DH): “I wanted to develop a non-hormonal solution, as low-tech as possible. My ambition is to allow as many people as possible to access contraception.”
Challenges Ahead
Several challenges remain before the STEOM device becomes widely available. The regulatory pathway requires extensive clinical trials to demonstrate safety and efficacy, with a target efficacy approaching 99% — comparable to vasectomy. Cultural attitudes toward male contraception will also need to evolve, a challenge the researchers acknowledge.
Importantly, the device does not protect against sexually transmitted infections, meaning condoms will remain necessary for STI prevention. Questions about potential discomfort during wear will only be answered during human trials.
What to Watch For
As vasectomy rates have surged — multiplying by 15 times in about 12 years in France, according to an EPI-PHARE study cited by Journal du Geek — the demand for male contraceptive options is clearly growing. The STEOM device, if successful, could offer men a middle ground between temporary methods and permanent sterilization.
“If mindsets have already changed, we will need to continue working on this,” Prasivoravong concluded. With preclinical trials imminent and a clear development roadmap, the next decade could transform the landscape of reproductive health.