Pharmacologic development of male hormonal contraceptive agents

Abstract

The world population continues to increase dramatically despite the existence of contraceptive technology. The use of male hormonal contraception may help in preventing un intended pregnancies and managing future population growth. Male hormonal contraception relies on the administration of exogenous hormones to suppress spermatogenesis. Clinical trials have tested several regimens using testosterone, alone or in combination with a progestin. These regimens were shown to be >90% effective in preventing conception and were not associated with serious adverse events.

Figure 1

The mechanism of action of male hormonal contraception. The normal stimulation of the hypothalamic–pituitary–testicular axis is highlighted with green arrows. Exogenous testosterone, alone or in combination with a progestin, mimics the negative feedback of endogenous testosterone at the hypothalamus and pituitary, thereby suppressing LH and FSH secretion. FSH, follicle-stimulating hormone; GnRH, gonadotropin-releasing hormone; LH, luteinizing hormone.

Figure 2

Mean sperm concentrations in men treated with 1,000 mg TU every 8 weeks alone (diamonds) or in combination with 150 mg (squares) or 300 mg (triangles) of MPA every 8 weeks (arrows). All 20 subjects in the TU/MPA groups achieved azoospermia by week 20 of treatment. MPA, medroxyprogesterone acetate; TU, testosterone undecanoate. Reprinted from ref. . Copyright 2004 The Endocrine Society.