Correlation between Sperm DNA Fragmentation and Motility Pa-rameters: A Comprehensive Study

To investigate the relationship between sperm DNA fragmentation (SDF) and sperm motility pa-rameters in men undergoing fertility evaluation.

This retrospective observational study in-cluded 589 men aged 18-50 years evaluated at a sin-gle 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 pa-rameters 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 ana-lyzed using Spearman's rank correlation, with Pearson's test performed as sensitivity analysis. Comparisons be-tween two groups (<20% vs ≥20%) were performed us-ing the Mann-Whitney U test. Comparisons among three fragmentation categories (<20%, 20-30%, >30%) were conducted using the Kruskal-Wallis test followed by Dunn's post-hoc analysis. A p-value <0.05 was consid-ered statistically significant.

The mean SDF was 23.5%. SDF demonstrat-ed 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 sper-matozoa (rho=0.335, 95% CI [0.261, 0.405], p<0.001).Samples with SDF ≥20% (n=276) showed significant-ly 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 ob-served across the three fragmentation categories.

Higher sperm DNA fragmentation levels were associated with impaired motility patterns, partic-ularly 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.