Abstract
Nowadays, the efficiency of the infertility treatment is relatively low. One of the cues to counteract this problem relies on the optimum selection of spermatozoa. We developed a new method (sperm selection assay (SSA)) based on the chemical attraction of spermatozoa that are at the best functional state. Additionally, the SSA leads spermatozoa to complete and/or acquire the competence to fertilize the egg. These effects are equally observed either in normal or subfertile semen samples. Those capabilities of SSA may improve the success of current infertility treatment.