The most frequent cause of male infertility is left varicocele. The surgical or laparoscopic approach for spermatic vein ligation is considered the best method of treatment. The approach to a clinically significant left varicocele associated with a right varicocele (frequently of a smaller size) is not univocal. We analyzed the seminal responses obtained in 65 patients with bilateral varicocele (grades 2 to 3 on the left side and grade 1 on the right side) assigned randomly to undergo unilateral or bilateral ligation. There were no significant differences between the 2 groups with regard to seminal recovery.