Currently, options for male contraception are limited to condoms, withdrawal, or vasectomy. An effective means of male birth control could reduce high rates of unplanned pregnancies and abortions. To date, the only male contraceptive drugs being tested in humans are hormonal agents that affect testosterone, the primary male reproductive hormone. These regimens could potentially have unwanted side effects in some individuals.
To try to find a non-hormonal alternative, researchers funded by the Contraceptive Discovery and Development Branch tested the effect of a chemical called JQ1 on sperm production and reproduction in male mice. JQ1 blocks the activity of a protein that is essential for sperm production.
Treating male mice with JQ1 reduced both the number of sperm and the sperm’s ability to move around. All of the JQ1-treated mice mated normally but did not impregnate females. The chemical did not affect males’ hormone levels, and its effects were completely reversible, so males previously treated with JQ1 fully recovered the ability to impregnate females. The resulting pups appeared to be normal and healthy.
These findings suggest that JQ1, or a similar compound, could be an effective non-hormonal means of contraception in human males (PMID: 22901802).