Sperm DNA fragmentation and male fertility: a retrospective study of 5114 men attending a reproductive center.

PURPOSE: The sperm DNA fragmentation index (DFI) was quantitatively measured and its relationship with age, semen quality, and infertility conditions was investigated. METHODS: Semen routine test and sperm DFI were performed in 2760 infertile male and 2354 male whose spouse experienced at least one unexplained miscarriage to analyze the correlation between sperm DNA damage, semen routine parameters, and age. RESULTS: Sperm DFI was significantly lower from patients whose wife experienced unexplained miscarriage compared to infertility males (p = 0.000). An inverse correlation between sperm DFI and sperm progressive motility was observed (rs = - 0.465, p = 0.000) and sperm DFI was positively correlated with age (rs = 0.255, p = 0.000). However, the correlation between sperm DFI and sperm concentration, semen volume, total sperm count, and motile sperm count were not proved. CONCLUSIONS: Sperm DFI is an important indicator for evaluating the quality of semen. Sperm DNA integrity testing is preferentially recommended to those who have decreased sperm progressive motility, especially older men. An integrative analysis of sperm DFI, sperm progressive motility, age, and infertility conditions can provide a more comprehensive assessment of male fertility.