Male contraception: a realistic option?

Area of Science:

• Reproductive Endocrinology
• Pharmacology of Contraception
• Andrology

Background:

• Male hormonal contraception aims to reversibly suppress spermatogenesis.
• Current methods require gonadotropin suppression, leading to androgen deficiency.
• Testosterone replacement is essential to counteract androgen deficiency.

Purpose of the Study:

• To review the principles of hormonal male contraception.
• To provide an overview of ongoing clinical trials for male contraceptives.
• To discuss the efficacy and limitations of current and developing hormonal agents.

Main Methods:

• Review of existing literature and clinical trial data on hormonal male contraception.
• Analysis of different hormonal formulations: injectables, implants, patches, gels, and oral agents.
• Assessment of efficacy based on spermatogenesis suppression (azoospermia/oligozoospermia) and testosterone levels.

Main Results:

• Hormonal male contraception relies on suppressing gonadotropins to halt spermatogenesis.
• Testosterone replacement is needed due to inhibited endogenous androgen production.
• Injectable testosterone with gestagens or implants show promise; other formulations (patches, gels, oral) have shown disappointing efficacy due to insufficient gonadotropin suppression.

Conclusions:

• Achieving azoospermia with exogenous testosterone alone is ethnicity-dependent.
• Additional agents are required for Caucasian men to achieve sufficient spermatogenesis suppression.
• Further large-scale, multi-center studies are necessary to validate the contraceptive efficacy of promising steroid combinations.