Abstract
Objective: To investigate the relationship between sperm DNA fragmentation (SDF) and sperm motility parameters in men undergoing fertility evaluation.
Methods: This retrospective observational study included 589 men aged 18–50 years evaluated at a single Brazilian andrology center between August 2021 and February 2024. Only the first semen sample per patient was analyzed. SDF was assessed using the sperm chromatin dispersion (SCD) test, and semen parameters were evaluated according to the sixth edition of the WHO Laboratory Manual. Data distribution was assessed using Shapiro–Wilk testing. As most variables were non-normally distributed, associations were analyzed using Spearman’s rank correlation, with Pearson’s test performed as sensitivity analysis. Comparisons between two groups (30%) were conducted using the Kruskal–Wallis test followed by Dunn’s post-hoc analysis. A p-value <0.05 was considered statistically significant.
Results: The mean SDF was 23.5%. SDF demonstrated a moderate inverse correlation with rapid progressive motility (rho=-0.289, 95% CI [-0.361, -0.213], p<0.001) and a moderate positive correlation with immotile spermatozoa (rho=0.335, 95% CI [0.261, 0.405], p<0.001). Samples with SDF ≥20% (n=276) showed significantly lower rapid progressive motility and higher immotility compared to those with SDF <20% (n=313) (p<0.01). Total motile sperm count was also reduced in the higher fragmentation group (p<0.01). Similar patterns were observed across the three fragmentation categories.
Conclusion: Higher sperm DNA fragmentation levels were associated with impaired motility patterns, particularly reduced rapid progressive motility and increased immotility. These findings support the integration of SDF testing as a complementary parameter in the evaluation of male fertility.