BACKGROUND AND OBJECTIVE: Vaginal yeast infections in women are usually caused by Candida albicans and, to a lesser extent, by Saccharomyces cerevisiae. Studies on C. albicans have shown that it can cause sperm agglutination which can lead to lowered fertility. This study was conducted to compare the effect of S. cerevisiae and C. albicans on the fertility of ICR mouse (Mus musculus) through sperm agglutination.

METHODOLOGY: Sperm agglutinating activity was examined by mixing different concentrations of S. cerevisiae (10, 10°, and 10 CFU/mL) and C. albicans (10", 10°, and 10 CFU/mL) separately with semen from male mice of ICR strain. Determination of the effect of S. cerevisiae and C. albicans on the fertility outcome of female mice was done by intravaginal inoculation of 20 uL of 104, 106, and 108 CFU/ml of the two yeast organisms and later allowed to mate.

RESULTS AND CONCLUSION: The study showed a statistically significantly higher percent sperm agglutination by S. cerevisiae than C. albicans at 10* CFU/ml but no difference was observed at 10° and 10 CFU/ml. No significant difference was observed in the number of sperm per agglutinate between the two yeast species at a=0.05. The concentration that exhibited the highest percentage of agglutinated sperm is 10° CFU/mL for both yeast. The most frequent type of agglutination observed in S. cerevisiae is the mixed type, while head-to-head type is most frequent in C. albicans. Both yeasts were able to cause a decline in the number of births in mice starting at 10 CFU/ml. While sperm agglutination could be one of the reasons for the infertility observed in mice, there may be other processes, mechanisms, and/or activities that could contribute to such an outcome.