Alleviation of acrosome reaction prematurity by sperm treatment with egg yolk

Abstract

To examine the effects of egg yolk on the spontaneous and ionophore-induced acrosome reaction (AR) and sperm-zona pellucida (ZP) binding in spermatozoa from patients with AR prematurity. Prospective analysis. Private hospital, public research center, and a university-based laboratory. In vitro fertilization patients selected on the basis of previous AR testing. None. Frequency of the AR, number of ZP-bound spermatozoa. The pretreatment of spermatozoa with egg yolk decreased the frequency of AR occurring spontaneously during subsequent sperm incubation in capacitating medium but did not modify the sperm response to ionophore. The egg yolk-treated spermatozoa also showed a greater capacity of binding the ZP than their untreated counterparts. The pretreatment of spermatozoa with egg yolk alleviates the sperm-ZP binding deficiency resulting from premature initiation of the AR and may be helpful in IVF with patients showing this anomaly.