Because it is outside of the body, the testis is cooler than other organs, a condition that’s important to sperm survival. Heat is toxic to sperm production. The cords transporting blood to and from the testis are arranged in a radiator-like “counter-current heat exchange.” A common cause of male fertility is varicose veins in the scrotum that heat the testis and disrupt sperm production.
Varicose veins in the scrotum are called a varicocele. Until the 1990s, doctors argued whether varicoceles were important to male fertility and whether treating them helped. It was discovered that treating varicoceles that were neither felt nor visible on physical exam by a doctor was not helpful. Varicoceles that could be felt or were visible would damage sperm production, and male fertility improved with treatment of these varicoceles.
Treating a varicocele usually involves an outpatient surgical procedure called a varicocelectomy, which may be done with the surgeon using magnifying lenses or the operating microscope to preserve the tiny arteries carrying blood to the testis. Dr. Fisch is an expert microsurgeon, and has done many varicoceles with excellent results. Check out a story of a couple struggling with infertility who turned to Dr. Fisch.