Sperm MTT Viability Assay: A New Method For Evaluation Of Sperm Viability

Document Type : Original Article


Embryology Department, Royan Institute, Tehran, Iran


Introduction: Sperm Viability Test is important in diagnosis and treatment of male infertility. The common test is E&N and HOST which they are based on membrane permeability and integrity. The aim of this study was to evaluate MTT Assay as a sperm viability test based on mitochondrial activity.
Materials and Methods: Washed sperm samples were co-incubated with MTT in different media and different times in order to obtain the best condition for carrying out MTT assay. Then coefficient of variation of MTT was obtained and sensitivity and specificity of each test were calculated. Then MTT and E&N and HOST were carried out on 57 samples from infertile patient referring into Isfahan Fertility and Infertility Center. Then correlation coefficient of these tests with each other and sperm motility were obtained using SPSS software statistical program.
Results: Ham's F-10 + 15 mM Hepes + 10% HSA at pH=7.4 at 37° c for 2 hours were the best condition for carrying out Sperm MTT Viability Assay in order to obtain optimal results. MTT assay showed a good significant correlation with HOST and E&N and sperm motility. All the test had high sensitivity but the specificity of HOST was less than that of E&N and MTT.
Conclusion: MTT assay appears to be a suitable sperm viability test with high sensitivity and specificity and low coefficient of variation. This test designed not only for differentiating but also selecting and sperating viable sperm from dead sperm. Therefore this test may have an application for intra-cytoplasmic immotile sperm injection which remains to be study.