Fuente: WIPO "milk" In a method for sorting spermatozoa, spermatozoa are stained with a fluorochrome dye. The fluorescence distribution of stained spermatozoa is complex: non-motile spermatozoa display a higher fluorescence than motile spermatozoa. The fluorescence profile of the motile spermatozoa is bimodal, and enables the spermatozoa to be sorted into distinct populations of motile spermatozoa.