[Internal quality control products for computer-assisted sperm analysis: Research and application]

To investigate the application of the self-made semen quality control (QC) product in internal QC of computer-assisted sperm analysis (CASA).

CASA was calibrated with high- and low-concentration commercially available semen QC product and meanwhile 15 samples of self-made mixed semen QC product were placed in 75 cryotubes containing liquid nitrogen, followed by CASA of the concentration, motility, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), wobble (WOB) and straightness (STR) of the sperm using standard procedures and 50 days of continuous monitoring. The Makler counting plate was used to measure the concentration and motility of the self-made sperm.

The coefficients of variation (CV) of the commercially available semen QC product at high and low concentrations were 6.18% and 7.85%, respectively. CASA showed that the concentration of the self-made QC product was (25.97 ± 1.41) ×10⁶/ml, with a CV of 5.42%, and the sperm motility, VCL, VSL, VAP, LIN, WOB and STR were (22.15 ± 1.75)% (CV = 7.9%), (59.18 ± 2.05) μm/s (CV = 3.46%), (26.79 ± 1.2) μm/s (CV = 4.48%), (34.98 ± 1.4) μm/s (CV = 4.01%), 46.81 ± 1.55 (CV = 3.3%), 60.52 ± 1.3 (CV = 2.15%) and 76.46 ± 1.98 (CV = 2.59%), respectively. The concentration and motility of the self-made sperm detected with the Makler counting plate were (34.39 ± 2.37) ×10⁶/ml (CV = 6.89%) and (38.04 ± 1.69)% (CV = 4.44%), respectively. Levey-Jennings QC charts were plotted for the indicators using the means and standard deviation.

The self-made internal QC product by liquid nitrogen cryopreservation is feasible and effective for monitoring the accuracy and precision of CASA-derived sperm concentration and motion parameters, and it has a smaller CV than the commercially available QC product in measuring sperm concentration.