RESUMO
Evaluation of male fertility is based predominantly on results from semen analysis and determination of the sperm concentration is one of the main parameters of the analysis. To assess the accuracy of sperm concentration measurements by Makler counting chamber, manual sperm counting of 55 semen samples were made using a Makler counting chamber, and compared with concentration values measured using an improved Neubauer hemocytometer according to the World Health Organization guideline (standard procedure). Results were classified according to the standard procedure before statistical analyses. Both values correlated well. Sperm concentration obtained with Makler counting chamber was not statistically different from those determined by improved Neubauer hemocytometer in semen samples with concentrations over 40 x 10(6)/ml. But using Makler counting chambers caused a shift concentrations, which were overestimated significantly (p less than 0.0001) in semen samples with concentrations less than 40 x 10(6)/ml. Overall, Makler chamber counts were 11.2 per cent higher. Although less complicated than the improved Neubauer hemocytometer method, measurement of sperm concentration by Makler counting chamber is an inaccurate method, especially in semen samples with concentrations less than 40 x 10(6).