Dual Trigger vs. hCG for Final Oocyte Maturation. A Prospective Randomized Controlled, Double-Blinded Study: Preliminary Results

Introduction: Human chorionic gonadotropin (hCG) is usually used at the end of controlled ovarian hyperstimulation as a surrogate LH surge to induce final oocyte maturation. Recently, based on retrospective studies, the co-administration of GnRH agonist and hCG for final oocyte maturation (dual trigger) has been suggested to improve IVF outcome and pregnancy rates.

Aim: The aim of the study was to determine whether co-administration of GnRH agonist and hCG in IVF cycles would improve the number of oocytes and oocyte quality compared to hCG alone.

Methods: A single center, prospective, randomized controlled, double-blinded clinical trial.

Normal responder patients were randomized either to receive hCG or dual trigger for final oocyte maturation. Results: 154 patients were included in the study, 77 patients in each arm. The age (35.9 vs. 35.7 p=NS) and AMH (20.7 pmol/l vs. 19.5 pmol/l P=NS) were comparable between the two groups. The number of eggs retrieved (12.9 vs. 10.6, p=0.02), MII (10.1 vs. 8.6, p=0.03) and zygotes (7.9 vs. 6.3, p=0.04) were significantly higher in the dual trigger group. The oocyte recovery rate ( oocytes/follicles≥11mm) was significantly higher in the dual trigger group compared to the hCG group (97% vs. 78% p=0.001). The number of blastocysts (3.9 vs. 3.1, p=NS) was comparable between the two groups. The clinical pregnancy rate and the ongoing pregnancy rate were similar in both groups.

Conclusions: The dual trigger increases the number of oocyte, mature oocytes and the number of zygotes compared to triggering with hCG alone in normal responder patients.