SwimCount Harvester™ versus Density Gradient Centrifugation: A Pilot Study exploring Sperm DNA Fragmentation and Motile Sperm Recovery.

PURPOSE: To compare SwimCount Harvester™, a non-centrifugal sperm selection system, with Density Gradient Centrifugation (DGC) in terms of sperm DNA fragmentation (SDF), agreement between analytical methods, and total motile sperm recovery. MATERIALS AND METHODS: This pilot study evaluated semen samples processed using DGC and SwimCount Harvester™. SDF was assessed in raw and processed samples using the Sperm Chromatin Dispersion (SCD; Halosperm®) assay, analyzed both manually and via computer-assisted sperm analysis (SCA® CASA). Agreement between manual and CASA classification (>20% threshold) was evaluated using Cohen's kappa with bootstrap confidence intervals (10,000 resamples). Total motile sperm count (TMSC) was compared between DGC and Harvester (n=36), and effect size was calculated using Cohen's d. RESULTS: Both DGC and Harvester significantly reduced SDF compared with raw semen (p<0.001 for all comparisons), with no significant difference between techniques (CASA p=0.219; manual p=0.341). Agreement between manual and CASA assessment improved following processing, reaching perfect concordance after Harvester (κ=1.00; bootstrap 95% CI 0.54-1.00). Harvester yielded significantly higher TMSC compared with DGC (p=0.001), with a large effect size (Cohen's d=0.81). CONCLUSION: SwimCount Harvester™ achieves SDF reduction comparable to DGC while significantly increasing motile sperm recovery. These findings support the potential of non-centrifugal sperm selection as an alternative to conventional methods. Larger studies are required to confirm these results and determine their clinical implications.