Question of the Day

Endometrial cups in the equine placenta secrete equine chorionic gonadotropin (eCG) between 40-120 days of gestation. They are formed from cells of the equine fetus that invade the endometrium to form cups.

eCG is a form of luteinizing hormone and, in horses, it has a superovulatory effect. eCG used to be called “pregnant mare serum gonadotropin.”