Abstract: Objective: To investigate the effect of gonadotropin-releasing hormone agonist (GnRH-a) trigger on the laboratory technical indicators of embryos during natural cycle in vitro fertilization (IVF) in patients with diminished ovarian reserve (DOR). Methods: A retrospective study was conducted to analyze the data of patients with DOR who underwent natural IVF cycles in the Reproductive Medicine Center of Women's Hospital Affiliated to Nanjing Medical University from January 1, 2018 to April 30, 2023. According to whether the GnRH-a trigger was used, the patients were divided into trigger group and non-trigger group, with 300 cycles in trigger group and 47 cycles in non-trigger group. A 1:3 propensity score matching was performed to compare the total number of oocytes retrieved, transferable embryos, high-quality embryos, 2PN fertilization rate, oocyte utilization rate, high-quality embryos rate and non-retrieved oocytes rate between the two groups Results: A total of 165 cycles were included (46 cycles in non-trigger group and 119 cycles in trigger group) after propensity score matching, and the high-quality embryo rate in trigger group was higher than that in non-trigger group (61.1% vs. 35.0%, P=0.045). There were no significant differences in the total number of oocytes retrieved, the number of transferable embryos, the number of high-quality embryos, the 2PN fertilization rate, the oocyte utilization rate and the unobtained rate between the two groups (all P >0.05). Conclusion: There is no significant difference in the total number of oocytes retrieved, transferable embryos, high-quality embryos, 2PN fertilization rate, oocyte utilization rate and non-retrieved oocytes rate between the GnRH-a trigger and non-trigger in DOR patients, but the trigger can improve the rate of high-quality embryos.