The struggle for male hormonal contraception.

The principle of male hormonal contraception is based on the suppression of LH and FSH and the replacement of testosterone to maintain androgenicity. The goal can best be achieved by testosterone alone or by testosterone in combination with a gestagen. The five clinical trials using pregnancy rates as end points and the one trial performed by the pharmaceutical industry are reviewed here. An ongoing large multicenter trial launched by WHO and the US CONRAD Programme will decide about the future of male hormonal contraception.