RESUMO
PIP: Various methods of contraception in men are reviewed. One of the methods of contraception is the use of hormonal agents (estrogens, androgens, antiandrogens, progestins, or their combinations), which block spermatogenesis. More advantageous is the use of nonhormonal agents (alpha-chlorhydrine, 6-chloro-6-deoxyglucose, salsosulfapyridine), which act on the process of sperm maturation in the epididymis. Plant extracts show marked contraceptive activity in men. The preparation gossypol isolated from cotton seeds and roots was found to inhibit male fertility. Various isomers of gossypol decreased sperm mobility by inhibiting the mitochondrial respiratory chain. Major side-effect of gossypol was hepatotoxicity. Glycosides isolated from the herb Tripterigium Wilfordii (TW) were found to have the antifertility activity. The antifertility effect of TW glycosides was dose- dependent: large doses were shown to inhibit spermatogenesis, while small doses were found to decrease sperm motility and viability. TW glycosides were free of toxic side-effects. Another approach to regulation of male fertility is the use of surgical methods of contraception including vasectomy. Development of less invasive and reversible surgical methods showed effectiveness of subcutaneous occlusion of vas deferens with various chemical substances (calcium chloride, p-butyl-2-cyanoacrylate). The best results were achieved with high molecular weight medical polyurethane.^ieng
