RESUMO
<p><b>OBJECTIVE</b>To investigate the effects of the metabolite produced by Trichomonas vaginalis on human sperm motility in vitro.</p><p><b>METHODS</b>Trichomonas vaginalis having been cultured, the culture solution containing metabolite was obtained by removing the protozoa, then diluted into 3 kinds of concentration. Sperm was obtained from 10 healthy fertile men by masturbation and prepared by swim-up technique to produce a spermatozoon solution of high motility. Every sperm sample was divided into 4 groups (A, B, C, D). Unused culture solution was added to Group A as control, and the other 3 groups (B, C, D) were respectively incubated with the above used culture solution at 3 kinds of concentration (1.2 x 10(9)/L, 6 x 10(8)/L, 1.2 x 10(8)/L). Measurements were carried out at 30 s, 1 h, 2 h, 4 h, 6 h by CASA.</p><p><b>RESULTS</b>Sperm motility decreased in both Group B and C markedly, and the effects displayed a concentration- and time-dependent manner.</p><p><b>CONCLUSION</b>The metabolite of Trichomonas vaginalis can reduce human sperm motility in vitro, and may be one of the causes of infertility.</p>