Male hormonal contraception.

Although women have traditionally shouldered the responsibility of contraception, up to a third of couples worldwide employ a male form of contraception (e.g., condoms or vasectomy). Some women are unable to use hormonal contraception; vasectomy is best considered irreversible; and long-term use of condoms is associated with a relatively high failure rate (pregnancy). Thus, a need exists for a safe, effective, reversible, well-tolerated male hormonal contraceptive agent. Two large multi-centre, multi-national trials sponsored by the World Health Organization in the 1990s showed that high-dosage exogenous testosterone provided contraceptive efficacy similar to existing female oral contraceptives. However, the supraphysiological dosages of testosterone used resulted in androgen-related adverse effects such as weight gain and suppression of high-density lipoprotein cholesterol levels. Subsequent efforts have been directed at combining testosterone with other agents, such as progestogens or gonadotropin-releasing hormone analogues, to decrease the dosage of testosterone (and thus androgen-related side effects) while achieving uniform azoospermia. This review discusses the latest developments in male hormonal contraception.