The use of GnRH agonist (GnRHa) triggering among high responders in order to reduce or eliminate OHSS is an example of an important breakthrough in the clinical management of IVF patients. Although GnRHa triggering was shown to be as effective as human chorionic gonadotropin (hCG) at inducing oocyte maturation more than 20 years ago, its use to trigger ovulation was not possible until the introduction of GnRH antagonists for pituitary suppression.