Objective: To evaluate the application of distilled water in sperm-counting and hypoosmotic swelling test.
Methods: Thirty-seven semen samples were collected and each was diluted by distilled water and sodium acid carbonate-formaldehyde solution, respectively. Then the hemacytometer was used for sperm counting. Meanwhile, the percentage of swelled sperm diluted by distilled water was compared with the result of hypoosmotic swelling test recommended by WHO. Another 26 semen samples were diluted by distilled water and hypoosmotic swelling solution respectively, and the percentages of the swelled sperm were compared.
Results: There was no significant difference either between the sperm concentrations obtained by distilled water and sodium acid carbonate-formaldehyde solution (P > 0.05) or between the percentages of the swelled sperm diluted by distilled water and hypoosmotic swelling solution.
Conclusion: Distilled water can not only replace sodium acid carbonate-formaldehyde solution for sperm-counting dilution but also be used as a hypoosmotic swelling solution.