The male contraceptive pill is not hormonal and drastically reduces spermatogenesis.

A non-hormonal male contraceptive with 99% efficacy and no side effects has been discovered after research carried out on mice. A team of researchers from the Gunda Georg Laboratory at the University of Minnesota presented these results at the American Chemical Society.

Since 1960, when the female contraceptive pill was approved, science began to conduct research to produce a male contraceptive pill. Compared to women, who have a multitude of contraceptives of all kinds, there were only two contraceptive methods aimed at men: vasectomy and condoms. According to Dr. Abdullah Al Noman, a graduate of the University of Minnesota responsible for presenting this research, men are interested in sharing contraceptive responsibility with women, and having a non-hormonal male contraceptive without side effects. The new male contraceptive pill is set to begin human trials this year and could be commercialized in the future.

The female pill is used to alter the menstrual cycle and can cause serious side effects: breakthrough bleeding, high blood pressure, headaches, nausea, etc. There are pills with two artificial hormones of estrogen and progestin and others with only progestin. Both hormones prevent ovulation by changing the levels of natural hormones that the body produces. Progestin makes the mucus around a woman’s cervix thick and sticky. This prevents sperm from entering the uterus.

In addition, female contraceptives also work through an anti-implantation mechanism, that is, abortive, which means that in some cases conception does occur, but the embryo cannot implant in the uterus because of the drug and dies. In this sense, the male pill would have the advantage of avoiding side effects in women and embryonic death caused by the anti-implantation effect of female contraceptives.

The researchers had focused their efforts on testosterone, the male hormone. Its inhibition causes side effects: weight gain, depression and increased LDL cholesterol, which increases the risk of heart disease. In search of an alternative approach to avoid these effects, the team of researchers identified “the RAR-α protein (Retinoic Acid Receptor alpha), a protein that is part of a group of three nuclear receptors that bind to retinoic acid (a derivative of vitamin A) and which is necessary for embryonic development, cell growth and differentiation, for example, for the formation of sperm

The study was carried out from 100 compounds capable of inhibiting RAR-α and the researchers found that only compound YCT529 could inhibit it effectively and without causing side effects. There are other studies that have already been carried out with drugs that inhibit the other two receptors RAR-β and -γ. Only the orally administered compound YCT529 reduced sperm count and prevented pregnancy with 99% efficacy. Furthermore, one month after discontinuation of the compound supply, the mice became fertile again.

What is concluded from these results?

These results are promising, since a non-hormonal method without side effects could have been found as a male contraceptive. Thanks to these good results, clinical trials in humans will be launched in 2022. This discovery marks an important stage in the offer of birth control and responsibility methods for men. But this does not preclude studies on new compounds, since what has worked in mice might not work in humans. On the other hand, it would be interesting to investigate the long-term effects, since taking this compound for years could perhaps be harmful. But this does not exclude studies on new compounds, as what has worked in mice may not work in humans. On the other hand, it would be interesting to investigate the long-term effects, since taking this compound for years could be harmful.

Bioethical assessment

Contraception is the intentional impediment of conception, that is, the encounter of the ovum with the sperm (although it has already been mentioned that sometimes female contraceptives fail to prevent such an encounter and then the mechanism that occurs to prevent pregnancy is anti-implantation rather than anovulatory).

Contraception dissociates love from fertility, seeking the exercise of sexuality without procreation. Although this male pill is not hormonal, it is contraceptive. Its mechanism of action prevents fertility, separating the two ends of the conjugal act: union and procreation. However, responsible paternity (maternity) has as its objective the exercise of a satisfactory sexuality for the couple, respecting that double meaning.

The convenient method for this is abstinence during the woman’s fertile period, which allows maintaining that unity between the unitive and procreative moments and at the same time postponing a pregnancy when the couple cannot afford it for various reasons.


Mévin Nduwimana

Master in Bioethics



Subscribe to our newsletter:

We don’t spam! Read our privacy policy for more info.