A varicocele is a varicose vein or engorged vein of the testicle or scrotum. These are typically congenital (born with it) and occur in 15% of men on the left side. They are often asympyomatic. If symptoms occur, there is typically a feeling of pain or heaviness that is worsened throughout the day or with exertion. These are also a common cause of male infertility, thought to cause sperm damage by making hindering temperature regulation in the testicle

If varicoceles are symptomatic or causing infertility, then surgical treatment is usually offered.