Hemizona assay: use of fresh versus salt-stored human oocytes to evaluate sperm binding potential to the zona pellucida.

The hemizona assay (HZA) has a high predictive value for in vitro fertilization (IVF) results. Oocyte quality plays a significant role in the validation of this test. The question was asked whether human salt-stored oocytes (up to 30 days) are damaged and subsequently lose their sperm binding capacity when compared to fresh human oocytes. Equivalent binding in both the salt-stored and the fresh group of oocytes was observed in the hemizonae incubated with normal semen as well as in their matching halves incubated with semen from an infertile man. Based on the results, we conclude that salt-stored oocytes (pH 7.0) give reliable information regarding sperm binding potential under HZA conditions.