GnRH-Agonist Ovulation Trigger in Patients Undergoing Controlled Ovarian Hyperstimulation for IVF with Stop GnRH-Agonist Combined with Multidose GnRH-Antagonist Protocol.

Objective: This study aimed to characterize those patients undergoing the stop gonadotropin-releasing hormone (GnRH)-agonist combined with multidose GnRH-antagonist protocol, with suboptimal response to GnRH-agonist trigger in in vitro fertilization (IVF) cycles.

Design: This is a cohort study.

Setting: The study was conducted in a university hospital.

Patients: All consecutive women admitted to our IVF unit from February 2020 through November 2020 who reached the ovum pick-up stage were reviewed.

Interventions: Triggering final oocyte maturation by GnRH-ag alone (GnRH-ag trigger group), or combined with hCG (dual trigger group), in patients undergoing the stop GnRH-agonist combined with multidose GnRH-antagonist protocol was performed.

Main Outcome Measure: The main outcome measure was LH level 12 h after the trigger.

Results: Five out of the 32 patients (15.6%) demonstrated suboptimal response as reflected by LH levels <15 IU/L 12 h after GnRH-agonist trigger. Moreover, while no differences were observed in oocyte recovery rate, maturity, or embryo quality between the different study groups (GnRH-ag trigger and dual trigger groups), those achieving a suboptimal response to the GnRH-agonist trigger (post-trigger LH <15 mIU/mL) demonstrated significantly higher number of follicles and peak estradiol levels at the day of trigger, compared to those with optimal response (post-trigger LH >15 mIU/mL).

Conclusions: The stop GnRH-agonist combined with GnRH-antagonist protocol enables the substitution of hCG with GnRH-ag for final oocyte maturation. However, caution should be taken in high responders, where the dual trigger with small doses of hCG (1,000-1,500 IU) should be considered, aiming to avoid suboptimal response (post-trigger LH levels <15 IU/L).