Association of sperm apoptosis and DNA ploidy with sperm chromatin quality in human spermatozoa

Objective: To examine the relationship among sperm apoptosis, sperm chromatin status, and DNA ploidy in different sperm fractions. Design: Prospective study. Setting: Reproductive research center in a tertiary care hospital. Intervention(s): Sperm prepared by density gradient were evaluated for sperm count, motility, apoptosis, and sperm chromatin assessment. Main Outcome Measure(s): Sperm count, sperm motility, toluidine blue (TB) results, DNA fragmentation index (%DFI), high DNA stainability, DNA cytometry, and early and late apoptosis. Result(s): Sperm motility was related to late apoptotic and subhaploid apoptotic sperm (r = -0.56 and -0.53, respectively). The sperm %DFI showed significant correlation with late apoptotic and subhaploid sperm (r = 0.62 and 0.68). TB-stained sperm were significantly correlated with late apoptotic sperm (r = 0.51). Significantly higher proportions of haploid sperm and light blue TB-stained sperm were seen in mature compared with immature fractions. Conclusion(s): Even in semen samples with low %DFI, semen processing results in a lower incidence of nuclear immaturity and subhaploidy, but the incidence of late apoptotic sperm remains unchanged. Therefore, simultaneous evaluation of apoptosis and sperm chromatin status is important for processing sperm in assisted reproductive procedures.