Varicocele and Male Fertility: What to Know

A varicocele, an enlargement of the veins within the scrotum, similar in nature to a varicose vein elsewhere in the body, is common enough that many men have one without ever knowing it. Its significance comes from being the single most frequently identified correctable cause of male infertility, which makes it worth understanding even though most varicoceles never cause a problem.

How common they actually are

Varicoceles occur in roughly 15 percent of all men in the general population, but the proportion is notably higher, around 35 to 40 percent, among men specifically being evaluated for infertility, and higher still among men with secondary infertility (difficulty conceiving after a prior successful pregnancy). This disproportionate representation in infertility evaluations is what establishes the connection, not that varicoceles are inherently rare or unusual.

Why they can affect fertility

The prevailing explanation is that pooled blood within the enlarged veins raises the local temperature around the testicle, since normal sperm production depends on the testicles being maintained at a temperature slightly below core body temperature. Elevated local temperature is believed to impair sperm production and quality over time, which is the mechanistic basis for the observed association between varicocele and reduced fertility in some men.

Not every varicocele needs treatment

Many varicoceles are entirely asymptomatic, cause no discomfort, and do not measurably affect fertility, particularly smaller ones. These are generally monitored rather than actively treated, since intervention carries its own risks and costs that are not justified without a clear indication. A varicocele identified incidentally, with no fertility concerns and no symptoms, does not automatically require treatment.

When treatment becomes appropriate

Treatment is generally considered when a varicocele is associated with abnormal semen parameters in a man actively trying to conceive, when it causes symptoms like discomfort or a dragging sensation, or in some cases of testicular size discrepancy in adolescents, where earlier intervention may help preserve future fertility potential. The specific decision depends on the size and grade of the varicocele, semen analysis findings, and the couple's fertility goals and timeline.

What treatment actually involves

Varicocelectomy, a surgical procedure to identify and tie off the affected, enlarged veins while preserving normal blood flow, is the traditional standard treatment, with a well-established track record. Varicocele embolization, a less invasive procedure performed by an interventional radiologist, blocking the problematic veins from inside the blood vessel rather than through surgical incision, is a viable alternative with its own advantages and considerations.

Setting realistic expectations

Treatment does not guarantee improved fertility for every man, but a meaningful proportion see measurable improvement in semen parameters afterward, particularly when the varicocele is judged to be a significant contributing factor to fertility difficulty rather than an incidental finding alongside other causes. Most major insurance plans, including Medicare, cover the evaluation and treatment of a varicocele when clinically indicated.