Varicocelectomy: Effect on Fertility

The varicocele is the single most commonly identified, correctable form of male infertility1. It occurs in approximately 15% of the normal male population and in 40% of those presenting for the evaluation of infertility1. A marked left sided predominance exists. This is most probably secondary to a combination of factors. First, the spermatic vein on the left side is 8–10 cm longer than the right, predisposing it to greater hydrostatic pressures, particularly in the erect position. Second, the entry of the spermatic vein into the renal vein on the left compared to its entry into the inferior vena cava on the right leads to relatively elevated pressures on the left for two reasons. The pressure gradient at the spermaticorenal junction is lower than at the spermaticocaval junction, in so far as the pressure in the renal vein is higher than in the vena cava2. In addition, the Bernoulli principle of fluid dynamics dictates that in any horizontally moving fluid, pressure increases as the velocity of flow decreases. The lower flow rate through the renal vein as compared to the vena cava produces less “forward draw” on blood traveling in the left spermatic venous system. The end result is elevated pressures in the left system. Therefore, man due both to anatomic considerations as well as evolutionary, in that he has assumed an erect posture, is predisposed to the formation of varicoceles.