Viability and function of human sperm in electrolyte-free cold preservation.

OBJECTIVE

To assess the viability and function of human sperm in electrolyte-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.

INTERVENTION(S): Ejaculated sperm were washed using the electrolyte-free Percoll gradient and were then preserved in 0.33 M glucose solution, 0.16 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 ejaculated semen and preserved at 4 degrees C.

MAIN OUTCOME MEASURE(S): Sperm tail morphology, motility, viability (eosin-Y stain), and the concentration of adenosine triphosphate (ATP) were analyzed.

RESULT(S): The number of sperm with normal tail form and the motility of sperm preserved in glucose solution (electrolyte-free cold preservation) were significantly (P < 0.01) higher for 4 weeks than those of sperm preserved in the other three media. The sperm viability in glucose solution was 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 glucose 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.