ABSTRACT
PURPOSE: This study aimed to investigate the association between sperm quality assessed by routine semen analysis and sperm DNA integrity assay. METHODS: In our cross-sectional study, a total of 318 men from the infertile couples were enrolled from December 2017 to March 2019 at the Hue Center for Reproductive Endocrinology and Infertility, Vietnam. General characteristics and semen parameters were detected. The sperm DNA fragmentation index (DFI) was estimated by the sperm chromatin dispersion (SCD) assay. A threshold of DFI 30% was applied to classify normal (DFI < 30%) or abnormal (DFI ≥ 30%) groups. The correlations between DFI and semen parameters were analyzed by Spearman's rank correlation coefficient. RESULTS: In the correlation analysis, DFI was significantly correlated with abnormal head and progressive motility, with a positive correlation with abnormal head (ρ = .202, P = .0003) and a weak negative correlation with progressive motility (ρ = -.168, P = .0027), respectively. In the bivariate analysis, DFI was associated with male age, smoking, and alcohol consumption with P < .05. CONCLUSIONS: The sperm DFI was not strongly correlated with conventional semen parameters. Therefore, a sperm DNA fragmentation assay should be performed as an additional step in the investigation of male fertility.
ABSTRACT
OBJECTIVE: Sperm cryopreservation has been widely used in assisted reproductive technology, as it offers great potential for the treatment of some types of male infertility. However, cryopreservation may result in changes in membrane lipid composition and acrosome status, as well as reductions in sperm motility and viability. This study aimed to evaluate sperm DNA fragmentation damage caused by conventional freezing using the sperm chromatin dispersion test. METHODS: In total, 120 fresh human semen samples were frozen by conventional methods, using SpermFreeze Solution as a cryoprotectant. Routine semen analysis and a Halosperm test (using the Halosperm kit) were performed on each sample before freezing and after thawing. Semen parameters and sperm DNA fragmentation were compared between these groups. RESULTS: There was a significant decrease in sperm progressive motility, viability, and normal morphology after conventional freezing (32.78%, 79.58%, and 3.87% vs. 16%, 55.99%, and 2.55%, respectively). The sperm head, midpiece, and tail defect rate increased slightly after freezing. Furthermore, the DNA fragmentation index (DFI) was significantly higher after thawing than before freezing (19.21% prior to freezing vs. 22.23% after thawing). Significant increases in the DFI after cryopreservation were observed in samples with both normal and abnormal motility and morphology, as well as in those with normal viability. CONCLUSION: Conventional freezing seems to damage some sperm parameters, in particular causing a reduction in sperm DNA integrity.
