Objective To investigate the correlation between human sperm DNA fragmentation index (DFI) and semen parameters, and evaluate the application value of DFI in male fertility. Methods Semen samples from 3020 male patients were collected. Sperm DNA fragmentation index (DFI) was detected by acridine orange staining and flow cytometry. Sperm concentration, total viability, progressive motility (PR) and the total number of sperm were calculated using computer-assisted semen analysis system (CASA). The semen volume was determined by weighing. Results There was no significant relationship between sperm concentration and DFI(r =0.003,P>0.05). There was a significant correlation between semen volume and DFI (r = 0.078, P <0.01), between the total sperm motility and DFI (r =-0.447, P<0.01), between the progressive motility (PR) and DFI (r =-0.444, P<0.01), between total number of sperm and DFI (r =0.069, P<0.01). All the differences were statistically significant (P<0.05). Conclusion The sperm DNA fragment index was positively correlated with semen volume and total number of sperm, but it was negatively correlated with total motility and PR. These indicates that semen parameters may provide a reference for evaluating sperm DNA integrity.

Objective To investigate quality control (QC) of Computer-aided Sperm Quality Analysis(CASA) in different laboratories for counting sperm concentration by manual counting, and ensure a standard of sperm concentration counting between different laboratories. Methods Sperm concentrations of 600 semen samples in three different hospitals were determined by manual counting and CASA from January 1, 2016 to March 31, 2016, the CASA parameters wereadjusted based on the results of manual counting. Subsequently, sperm concentrations of other 600 semen samples in three different hospitals were determined by manual counting and CASA from April 1, 2016 to June 30, 2016. The results were comparatively analyzed. Results (1) From January 1, 2016 to March 31, 2016, there was no difference in the results of sperm concentration of 400 semen samples from Shanghai First Maternity and Infant Hospital between manual counting and CASA (P>0.05); the level of sperm concentration in 100 semen samples from Children and Women's Health Care Hospital in Pudong New Area using manual counting was higher than that using CASA (P<0.05); the level of sperm concentration in 100 semen samples from Children and Women's Health Care Hospital in Minhang Area using manual counting was lower than that using CASA (P<0.05). (2) CASA parameters in different laboratories were adjusted based on the above results. from April 1, 2016 to June 30, 2016, there was no difference in the results of sperm concentration of 400 samples from Shanghai First Maternity and Infant Hospital between manual counting and CASA (P>0.05). There was no difference in the results of sperm concentration of 100 samples from Children and Women's Health Care Hospital in Pudong New Area between manual counting and CASA (P>0.05). There was no difference in the results of sperm concentration of 100 samples from Children and Women's Health Care Hospital in Minhang Area between manual counting and CASA (P>0.05). Conclusion The accuracy and consistency of sperm concentration counting between different laboratories can be significantly improved by adjusting the CASA parameters according to the results of sperm concentration by standard manual counting regularly.