EFFECT OF PROGESTERONE ON HUMAN ZONA-PELLUCIDA SPERM BINDING AND OOCYTE PENETRATING CAPACITY

Objective: To determine if sperm exposure to P produces an enhancement in its fertilizing capacity. Design: Sperm from fertile donors were e xposed to P at 0.1 and 1.0 mug/mL for 1 or 24 hours. The effects on hy peractivated (HA) motility at 1 and 4 hours, acrosome reaction (as det ermined by Pisum sativum agglutinin or T6/antibody techniques), on hum an zona pellucida binding (by using the hemizona assay), and on the pe netrating ability (by using the zona-free hamster ova assay) were eval uated. Results: Exposure to P at 1.0 mug/mL enhanced HA motility after 1 and 4 hours of P exposure, the acrosome reaction after 24 hours' in cubation, the number of sperm bound/hemizona after 1-hour incubation, and the penetration rates in the hamster ova assay at both incubation intervals. Conclusion: Sperm exposure to P enhances its fertilizing ca pacity in fertile men, and further investigation is warranted as a pos sible treatment for male factor patients.