Our objective was to study antisperm antibody bound to the acrosome region during in vitro capacitation and to determine whether acrosome-antibody free sperm can be obtained from previously acrosome-antibody-coated sperm. The spermatozoa from a selected series of 14 patients were tested for sperm antibodies bound to the sperm surface using d-IBT and focusing on the acrosome positivity. The tests were carried out before the incubation and after 3, 6, 9, and 12 h of incubation in Tyrode's solution with 0.5% human serum albumin as the capacitation medium. Tests to evaluate acrosome region, sperm motion parameters, and zonae binding ability were carried out. In this way we were able to evaluate sperm function during capacitation protocol. The patients were 14 subjects selected according to good seminal characteristics, good post-rise sperm parameters, and high percentage of ASA bound to the sperm surface. In all cases the results showed that antisperm antibodies bound to the acrosome region were shed prior to the acrosome reaction. During sperm capacitation in human a modification, migration, or shedding of plasma membrane molecules takes place. The presence of antibodies in such an important area of the sperm head could certainly interfere in the fertilization process. Our data indicate that in vitro capacitation could provide an in vitro therapy capable of eluting antibodies from the acrosome region.