The correlation between male age, sperm quality and sperm DNA fragmentation in 320 men attending a fertility center

To investigate the effects of male aging on sperm quality and sperm DNA fragmentation.

The ejaculates of 320 unselected men attending a fertility clinic and, as a control, 84 normozoospermic men without any history of ART were analyzed according to WHO guidelines. Sperm DNA fragmentation was measured by flow cytometry after staining with propidiumiodide.

The patients were divided into four groups: <30 years, 30-35 years, 36-39 years and >or=40 years. Sperm motility decreased with increasing age whereas sperm concentration, morphology, and DNA fragmentation fluctuated throughout the four groups both among patients and among controls. However, we could not detect any significant correlation between male age and conventional semen parameters or sperm DNA fragmentation, respectively, neither in the patients' group nor among the controls. This also applies to a classification of patients and controls into only two age groups with a cut-off point at 35 years.

Our findings suggest that neither the routinely assessed semen parameters nor the amount of spermatozoa with fragmented DNA are affected by male age.