After a false start that saw trials halted because of side effects and safety concerns, it seems major research into a contraceptive pill for men has developed a tablet that’s safe and effective. 

As the Guardian reports, the pill is DMAU, its chemical name dimethandrolone undecanoate. As with contraceptive pills used by women, it’s made up of a combination of hormones – a progestin and androgen (like testosterone). Alongside the pill, scientists are developing contraceptive gels and injections for men. 

The idea of contraceptive pills for men has been floating about for some time now. Some participants in a 2016 study flagged side effects including depression and mood swings, acne, libido changes, and more – much like those women deal with when using hormonal birth control. One participant died by suicide, and another didn’t regain sperm function.

This recent study for a once-daily pill for men was carried out with groups in Washington and California. 83 volunteers aged between 18 and 50 did the month-long study. It successfully targets parts of the brain that lower sperm count. According to University of Washington researchers, subjects didn’t report any major symptoms or ill effects. There was however noted weight gain and changes in cholesterol, although nothing concerning.

The research examined ways around what previous studies had encountered – for example, men’s bodies clear quicker than women’s, meaning men would have to take twice the number of pills each day for the same effect. Additionally, that testosterone levels can cause liver inflammation. Researchers added another fatty acid, undecanoate, to slow clearance, meaning the pill had a much longer and focused effect to prevent pregnancy. 

Given what we know about the serious problems surrounding women’s contraception – the danger of blood clots, its erosion of mental health – this could be a revolutionary venture for sexual health.