In conclusion, our study suggests that dual trigger of GnRH-a and low-dose HCG (2,000 IU) could improve the reproductive outcome (higher quality embryo rate) and prevent severe OHSS among the high ovarian responders in GnRH-antagonist protocols, compared to GnRHa trigger or HCG trigger alone. Here, GNRH1 is linked to ovarian hyperstimulation syndrome.