Evaluation of Resazurin Reduction Test Results and their Correlation with Conventional Semen Parameters:A Large Scale Study

Resazurin reduction test (RRT) was performed on semen samples obtained from 500 patients attending tlie infertility clinic and 125 proven fertile males. The results of RRT were determined visually using resazurin colour chart. These results were compared with those of sperm parameters analysed by conventional methods to validate the utility of the test in infertility practice. In subfertile specimens (oligozoospermic, asthenozoospermic and oligoasthenozoospermic), the RRT grade ranges from 1 to 4 and in normozoospermic and fertile samples it was from 5 to 11. The highest correlation of RRT grade was with sperm motility (r=0.924, P<0.001), concentration (r=0.860, P<0.001), morphology (r=0.661, p<0.01) and viability (r=0.656, P<0.01). RRT grade > 5 had a sensitivity of 94.22% for a sperm concentration of > 20x10⁶/ml and > 40% motility, and specificity of 94% for a sperm concentration < 20x10⁶/ml and < 40% motility. These results suggest that the RRT is very simple and reliable test and it can be used in any andrology laboratory as an alternative to the existing semen analysis.