Received November 20, 2020
Accepted May 22, 2021

Objective: During in vitro fertilization (IVF) cycles, final oocyte maturation is usually triggered by human Chorionic Gonadotropin (hCG) for its known effect to mimic Luteinizing Hormone (LH) surge However, with the widespread use of the ‘antagonist protocol’, Gonadotropin Releasing Hormone agonist (GnRHa) is being more commonly employed as a trigger in order to minimize or eliminate the risk of ovarian hyper-stimulation syndrome (OHSS). Many studies proved its efficacy in inducing oocyte maturation and its safety in preventing OHSS in high-risk groups. Moreover, some studies showed that GnRHa trigger may improve oocyte yield. This study aimed to further explore any beneficial effect of adding GnRHa to hCG (dual trigger) on oocyte yield and fertilization rate in normal responder women. Method: the data of 127 patients on antagonist protocol (67 dual trigger and 60 HCG trigger) were reviewed and analyzed retrospectively. Results: The number of oocytes, the number of MII oocytes and the number of fertilized oocytes were all significantly higher with the dual trigger protocol compared to hCG only trigger. However, there is no significant difference in clinical pregnancy rate. Conclusion: Using dual trigger improved the number and quality of oocytes, and fertilization rate in normal responders.