In a research we were analysing the motility of human spermatozoa before and after two-step and ultrarapid cryopreservation of semen sample. A prospective comparative study was performed on 27 fresh semen samples. From this group, 15 men were diagnosed with normozoospermia and 12 with asthenozoospermia. Each semen sample was divided on 4 aliquotes. First two aliquotes were diluted with glycerol medium (Sperm Freeze Medium). Another two aliquotes were diluted with TEST-yolk buffer, which contains glycerol and egg yolk. In every group, one aliquot was frozen with two-step method and another one with ultrarapid method. After thawing, the motility of spermatozoa was evaluated with computer analysis. The main question was if ultrarapid freezing gives statistically similar results in postthaw motility comparing to two-step cryopreservation method. Results have shown the same level of postthaw motility and progressive motility of spermatozoa. There was also the same level of curvilinear velocity after both methods of cryopreservation and after the use of both cryoprotectants. Ultrarapid cryopreservation of microdrops could be appropriate method for freezing small volumes of semen sample, even if the motility of spermatozoa is low.
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