To evaluate whether co-treatment of repeated GnRHa triggers with GnRH antagonist protocols can improve the clinical outcomes in in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET) procedures. In this retrospective study, 712 Chinese Han women aged 20-42 undergoing autologous IVF/ICSI-ET with a flexible GnRH antagonist protocol were analyzed. The 735 cycles were split into the single (n = 238) and the repeated (n = 497) GnRHa groups. In the single GnRHa group, 0.2mg of triptorelin was given for oocyte maturation, whereas in the repeated GnRHa group, two doses of 0.2mg were administered 12h apart. PSM design was used for a fair comparison. The main study outcomes included the clinical pregnancy rate (CPR), live birth rate (LBR), good-quality embryo rate, and fertilization rate. Multivariate logistic regression analyses were used to identify all potential factors affecting clinical outcomes. Post-PSM, analysis of 159 cycles per group showed the repeated GnRHa group outperforming the single GnRHa group in IVF fertilization rates (71.5% vs. 67.7%, P < 0.05) and good-quality embryo rate (47.1% vs. 43.7%, P < 0.05). Furthermore, the repeated GnRHa group achieved higher CPR (72.6% vs. 53.4%, P < 0.05) and LBR (59.7% vs. 43.8%, P < 0.05) in FET cycles. Multivariate logistic regression indicated a significant negative correlation between the use of a single GnRHa trigger and both clinical pregnancy (OR = 0.382, P < 0.05) and live birth (OR = 0.518, P < 0.05). Our study reported that individuals who received a repeated GnRHa trigger exhibited higher CPR and LBR during FET cycles compared to those who received a single dose GnRHa trigger.