Advances in male hormonal contraception

New male contraceptive options are urgently needed. Safe, effective and fully reversible methods of male contraception would be useful for monogamous couples who are trying to regulate their family size. In addition, an effective male hormonal contraceptive that could be implanted or injected as a long-acting formulation every 3-6 months would be useful in countries where limiting population growth has become a public policy imperative. Male hormonal contraception is based on the same principles as traditional oestrogen-progestin female oral contraceptives. Both spermatogenesis and ovulation are dependent upon normal secretion of the pituitary gonadotropins, follicle stimulating hormone (FSH) and luteinizing hormone (LH). Exogenous gonadotropin-releasing hormone (GnRH) analogues and sex steroid hormones such as testosterone CO and progestins suppress gonadotropins and spermatogenesis. Two large multicentre trials demonstrated that weekly administration of high-dosage T was very effective in suppressing gonadotropins and spermatogenesis and conferred an overall contraceptive efficacy comparable to female oral contraceptives. Studies of combination regimens of lower-dosage T plus a progestin or a GnRH analogue have demonstrated greater suppression of spermatogenesis than the World Health Organization trials of high-dosage T. Most of these male hormonal contraceptives have been associated with modest weight gain and suppression of serum high-density cholesterol (HDL) levels. In this article, we review the new developments in male hormonal contraception.