VIABILITY AND FUNCTION OF HUMAN SPERM IN ELECTROLYTE-FREE COLD PRESERVATION

Objective: To assess the viability and function of human sperm in elec trolyte-free cold preservation. Design: Prospective comparative study. Setting: Andrology laboratory of our hospital. Patient(s): Ten semen samples obtained from patients attending our infertility clinic. Inter vention(s): Ejaculated sperm were washed using the electrolyte-free Pe rcoll gradient and were then preserved in 0.33 M glucose solution, 0.1 6 M NaCl solution, 0.16 M KCl solution at 4 degrees C for 4 weeks. As a control, TEST (TES and Tris) yolk buffer (TYB) was added to the ejac ulated semen and preserved at 4 degrees C. Main Outcome Measure(s): Sp erm tail morphology, motility, viability (eosin-Y stain), and the conc entration of adenosine triphosphate (ATP) were analyzed. Result(s): Th e number of sperm with normal tail form and the motility of sperm pres erved in glucose solution (electrolyte-free cold preservation) were si gnificantly (P < 0.01) higher for 4 weeks than those of sperm preserve d in the other three media. The sperm viability in glucose solution wa s 75.5%, 65.4%, and 51.3%, after 1, 2, and 4 weeks, respectively. The ATP concentration after 1, 2, and 4 weeks remained 64.2%, 53.0%, and 4 .3% of the prestorage value, respectively, in the sperm stored in gluc ose solution. Conclusion(s): The morphology, motility, viability, and ATP concentration of sperm in electrolyte-free cold preservation were substantially better than those in NaCl solution, KCl solution, or TYB for 2 weeks. ((C) 1998 by American Society for Reproductive Medicine. ).