RESUMO
PURPOSE: To investigate the effects of male ageing on DNA fragmentation and chromatin packaging in the spermatozoa of oligoasthenoteratozoospermic (OAT) patients. METHODS: Sixty-one OAT patients and 49 men with proven fertility (controls) were included in the present study. DNA fragmentation was detected by terminal deoxynucleotidyl transferase-mediated dUTP-nick end labelling (TUNEL) assay, while chromatin packaging was assessed by chromomycin A3 (CMA3) staining. RESULTS: In the patient group, semen volume, percentage of normally shaped spermatozoa and sperm motility decreased significantly (P<0.05) with age, while sperm concentration and the percentage of TUNEL and CMA3 positive spermatozoa showed a statistically significant increase with age (P<0.05). In the control group, conventional semen parameters as well as DNA fragmentation and chromatin packaging did not show a statistically significant change with age (P>0.05). CONCLUSION: Increased age in OAT patients is associated with an increase in sperm concentration, DNA fragmentation and poor chromatin packaging, as well as a decline in semen volume, sperm morphology and motility.