Glycoprotein that regulates critical steps during fertilization and also has immunomonomodulatory effects. Four glycoforms, namely glycodelin-S, -A, -F and -C have been identified in reproductive tissues that differ in glycosylation and biological activity. Glycodelin-A has contraceptive and immunosuppressive activities (PubMed:7531163, PubMed:9918684). Glycodelin-C stimulates binding of spermatozoa to the zona pellucida (PubMed:17192260). Glycodelin-F inhibits spermatozoa-zona pellucida binding and significantly suppresses progesterone-induced acrosome reaction of spermatozoa (PubMed:12672671). Glycodelin-S in seminal plasma maintains the uncapacitated state of human spermatozoa (PubMed:15883155).