RESUMEN
<p><b>OBJECTIVES</b>To evaluate the application of Coomassie brilliant blue (CBB) G250 staining for the detection of human sperm deformity rate, rate of intact acrosome and acrosome reaction.</p><p><b>METHODS</b>The smear of spermatozoa before and after capacitation and induced acrosome reaction with progesterone (P) were stained with 0.05% CBB G250 and Wright-Giemisa solution respectively, and visualized with light microscopy. The deformity rate of spermatozoa, rate of intact acrosome and acrosome reaction were calculated.</p><p><b>RESULTS</b>There was no any difference in detection of deformity rate of spermatozoa and rate of intact acrosome with CBB G250 and Wright-Giemisa staining(P < 0.05). The sperm population of acrosome reaction with induced P was divided by CBB staining into two types: positive staining with dark violet blue on acrosome cap and pale or negative staining on the same area. The rate of the latter was increasing with increasing inductive time, maybe representative of the rate of acrosome reaction. The mean rate was(75.1 +/- 3.8)% after induced for 1 h.</p><p><b>CONCLUSIONS</b>CBB G250 staining is a reliable method for assessment of the human sperm morphology and acrosome reaction.</p>