Comparison of resazurin test results with various sperm parameters.

The resazurin reduction test was performed on semen samples from 83 untreated infertile and 9 pregnancy-confirmed fertile males, and the results were compared with other sperm parameters. The highest correlations with resazurin grade were found for motile sperm concentration (r = 0.65, P < 0.001), per cent motility (r = 0.58, P < 0.01), and percentage of swollen sperm (r = 0.57, P < 0.01). There were also significant but weak correlations between resazurin grade and both sperm concentration and linearity. There was a significant difference in the rate of positive tests between samples from normozoospermic and fertile males, and samples from patients exhibiting abnormal semen parameters (P < 0.001). These findings indicate that the resazurin test may be able to predict those males who may be fertile despite an abnormal semen analysis, and therefore, the test may be useful in the evaluation of the infertile patient as a part of a comprehensive male fertility assessment.