Analysis of the correlation between sperm DNA integrity and conventional semen parameters in infertile men

Objective: A male factor is responsible in approximately 30-40% of couples receiving infertility treatment. Routinely, such couples undergo semen analysis including parameters such as sperm count, motility and morphology. Generally, the analysis of sperm DNA damage, shown to have a significant clinical importance by many studies, is recognized as an advanced test that is not included in routine infertility tests. Intracytoplasmic sperm injection (ICSI) method, commonly employed in the current infertility treatment protocols, lowers the fertilization rate, however, fertilization can occur even with a damaged DNA which is known to pose a risk in the subsequent pregnancy period. The relation between sperm morphology and the degree of sperm DNA damage has not yet been understood clearly. In this study, we aimed to investigate the association between routine semen analysis and sperm DNA integrity assay, another advanced but costly method.

Material and methods: The degree of DNA damage was compared with the results of semen analysis, based on the WHO criteria, in 399 male patients who received comet assay for sperm DNA integrity. The statistical correlation analyses were performed with Windows SPPS statistical package program.

Results: Accordingly, the sperm DNA damage was found to be correlated with all 3 parameters (sperm count, forward motility, and morphology) examined by the semen analysis (p<0.001). Total sperm DNA Damage Count (TDC) was 226, 216, and 210 arbitrary units (AU) in patients with a sperm count <15 mil/mL, forward moving motility <32%, and normal morphology <4%, respectively. The difference with the normal individuals was statistically significant (p<0.001).

Conclusion: In light of the comet assay results, higher degree of sperm DNA damage is associated with significant impairment of all seminal parameters.