Pathophysiology of varicoceles in male infertility.

Varicoceles are found in 19 to 41% of infertile men, and is one treatable form of male infertility. The mechanism by which varicoceles cause the variable effect on male infertility and spermatogenesis is still unknown. Experimental animal models play a useful (but limited) role due to the sudden and variable iatrogenic nature of the varicoceles and the duration of the studies. Much of the human data are derived by the characterization of associated differences in measurable parameters between men with and without varicoceles. The role of hyperthermia, testicular blood flow and venous pressure changes, reflux of renal/adrenal products, hormonal dysfunction, autoimmunity, defects in acrosome reaction, and oxidative stress, in the pathophysiology of varicocele will be discussed.