A varicocele is a collection of swollen, enlarged veins—varicose veins—in the scrotum. The condition is caused by leaking valves in the veins that carry blood away from the testes, although there is usually no identifiable reason for the leakage.
Varicoceles most commonly occur on the left side of the scrotum. There may be no obvious symptoms, or they may include a swelling that is described as “feeling like a bag of worms,” and an aching pain in the scrotum. The affected side of the scrotum may also hang lower than normal.
A varicocele may also reduce fertility.
Small, painless varicoceles often disappear by themselves.
Larger ones, those causing discomfort, or varicoceles that affect fertility may be treated by surgery to tie off swollen veins.