To evaluate the inheritance of varicoceles through examination of first-degree relatives of patients with known varicoceles.

A total of 44 patients with a known varicocele had available first-degree relatives (n = 62) examined for the presence of a varicocele between October 1997 and November 2003. An additional cohort of 263 men presenting for vasectomy reversal without a history of subfertility or varicocele was used as the control group. Varicocele grade and the presence of bilateral varicoceles were examined as predictive factors for inheritance.

Of the 62 first-degree relatives of patients with a known varicocele, 35 (56.5%) had a clinically palpable varicocele on physical examination. This was significantly greater than the 18 (6.8%) of 263 men in the control group (P <0.0001). Of the first-degree relatives, 20 (74%) of 27 brothers, 13 (41%) of 32 fathers, and 2 (67%) of 3 sons had palpable varicoceles. Neither varicocele grade nor bilaterality was predictive of inheritance in these first-degree relatives.

The increase in varicocele prevalence is significant in the first-degree relatives (particularly brothers) of patients with known varicoceles. Given the detrimental effect of varicoceles on spermatogenesis and steroidogenesis, patients should be counseled about this increased risk in male family members.