A varicocele is a collection of swollen veins in the scrotum. It is a common condition, occurring in about 25% of young men, and usually causes only minor symptoms. In some men, however, a varicocele is associated with more severe pain which can be troublesome and interfere with normal activities. Varicoceles can also be associated with reduced fertility and are therefore commoner in those men suffering from fertility problems. Varicoceles occur because of a problem with the valves in the veins which carry blood from the scrotum and testicles. The condition, therefore, shares some similarities with varicose veins in the legs, and pelvic congestion syndrome in females.