Fertility regulation in the male.

The current state of research into new methods of male contraception is reviewed, with special emphasis on the efforts of the WHO Special Programme of Research, Development and Research Training in Human Reproduction. The article concentrates mainly on the development of orally administered or injectable substances capable of either (a) interfering with the hormonal control of testicular function, (b) disrupting spermatogenesis by direct influence on testis function, or (c) interfering with the fertilizing ability of the sperm and their transport. It is concluded that, despite the numerous areas of research currently being pursued, the availability of a new male contraceptive remains several years away.