Effect of microsurgical varicocelectomy on sperm DNA fragmentation in infertile men

ObjectivesTo examine the effect of microsurgical varicocelectomy on the sperm DNA damage in infertile men.SettingPrivate clinical practice.DesignProspective study.Participants and methodsEighty-one consecutive infertile men with clinically palpable varicocele. They underwent microsurgical inguinal varicocelectomy. Sperm DNA fragmentation was measured using TUNEL assay before and 6 months following surgery.Main outcome measuresChange in the percentage of sperm with damaged DNA.ResultsSix months following surgery, the percentage of sperm with DNA fragmentation was significantly decreased (21.5 ± 11.2 vs. 13.1 ± 14.3, P < 0.001). Eighteen patients had a preoperative DNA fragmentation index greater than 30%. In 16 (88.9%) of these patients, the DNA fragmentation index decreased following varicocelectomy below 30%.There was also a significant increase in sperm density (13.4 ± 11.7 million/ml before surgery vs. 20.2 ± 17.6 million/ml after surgery, P < 0.01), total motility (27.3 ± 15.6 vs. 39.4 ± 14.2, P < 0.001), progressive motility (9.5 ± 16.3% vs. 16.5 ± 14.3%, P < 0.01), and normal sperm forms (12.3 ± 5.9 vs. 14.7 ± 7.4, P = 0.03).ConclusionsDNA fragmentation index is known to be a more biologically stable parameter compared with normal semen parameters. Improvement in sperm DNA fragmentation is an evidence of the ability of varicocelectomy to improve fertility potential of infertile men. Further studies are invited to examine the clinical effect of the reported improvement.