Male hormonal contraception.

Male hormonal contraception, based on the suppression of both gonadotropins, follicle-stimulating hormone and luteinizing hormone, resulting in marked decrease in sperm production, is designed for couples in stable relationships where the male partner desires to assume family planning responsibilities using reversible methods. Two large scale, multicenter studies that used testosterone injections as the prototype male hormonal contraceptive demonstrated when azoospermia and/or very severe oligozoospermia were attained, contraceptive efficacy was equivalent to female hormonal methods. Current studies aim to find the androgen alone or androgen plus progestin preparations that are most efficacious, user friendly, and with least potential adverse effects. It is likely that injections or implants of androgens either alone or with progestins will become the first male hormonal contraceptive available within this decade. Further research and development include the use of selective androgen and/or progestin receptor modulators, nonpeptide GnRH antagonists, and agents with local actions on the testis for male contraception.