GNRH1 and ovarian hyperstimulation syndrome: GnRH agonists were commonly used in the past; however, in recent years, GnRH antagonists have become the standard of care in COS treatment due to several advantages: greater patient friendliness, shorter duration of administration, improved convenience [2], and enhanced safety through the reduction or elimination of ovarian hyperstimulation syndrome (OHSS) via GnRH agonist triggering and a freeze-all policy [3].