Accuracy of computer-assisted semen analysis in prefreeze and post-thaw specimens with high and low sperm counts and motility

Objectives. We evaluated the accuracy and precision of computer-assisted semen analysis (CASAs) to determine whether variations in the CASA results were related to the type of analyzer or to the type of specimens analyzed. Methods. Semen specimens were analyzed manually and by CASA before freezing and after thawing. Multiple ejaculates (220 semen specimens) from normal healthy donors (n = 8) and 131 semen specimens from 57 patients with cancer were assessed. Results. The differences between CASA and manual sperm counts and percent motility were higher in prefreeze and post-thaw specimens at sperm concentrations of less than 20 x 10(6)/mL. The differences between CASA and manual results were significant for cancer patients, compared with normal donors (P < 0.01). Conclusions. CASA results are unreliable at sperm counts of less than 20 x 10(6)/mL and post-thaw motility is generally underestimated by CASAs. (C) 1998, Elsevier Science Inc. All rights reserved.