Varicocele and male subfertility.

Unilateral and bilateral subclinical varicocele was found by internal spermatic venography in 10 of 30 men with stress-pattern semen and normal endocrine profiles. Seven of the 10 had no clinical evidence of varicocele. Right-sided varicocele may be almost as common as varicocele on the left and may be responsible for much of the bilateral effect of clinical left-sided varicocele. Transjugular venography has a low morbidity rate and can be used to clarify the relation between subclinical varicocele and infertility. The technique also permits nonsurgical treatment of varicocele.