To study the postoperative recurrences of varicocele and the relationship between recurrences and sperm variables, we reexamined postoperatively 48 patients aged 14-56 years (mean: 25 years); the patients returned within a time range of 4 to 36 months. All the patients underwent physical examination, B-mode, color and power Doppler sonography (US); the images were acquired with the patient both supine and upright, both at rest and during Valsalva maneuver. We studied the incidence of recurrences and their bilaterality, the presence of reflux with or without functional maneuvers, associated conditions, surgical complications and the improvement of sperm variables; color and power Doppler findings were compared. The incidence of recurrences (28) and that of major complications (2) were related to the type of surgery: thus, no complications but 26 recurrences were found in the patients with spermatic vein ligation, versus only 2 recurrences but also 2 major complications (1 testicular ischemia and 1 hydrocele) in the patients with ligation of the spermatic cord venous channels. A right varicocele was found in 12 patients, which confirmed the frequent bilaterality of this condition; 8 patients with recurrences had improved sperm variables and 6 presented associated conditions. Our trial confirms that B-mode US, combined with color and power Doppler, can show recurrences, bilaterality, surgical complications and associated conditions and emphasize the role of these exams in the postoperative follow-up of varicocele. However, no method alone, without the evaluation of sperm variables, permits to select the patients to be reoperated on.