CGA and ovarian hyperstimulation syndrome: Similarly, equine chorionic gonadotropin (ECG) and HCG were used to establish a rat model of OHSS via different injection approaches (Ujioka et al., 1997), and intraperitoneal injections of multiple hormones (PMSG, HMG, FSH, and HCG) were used to develop another rat model (Ajonuma et al., 2005).