Comparative analysis of hCG and dual-trigger protocols in IVF for advanced maternal age women: a single‑center retrospective cohort study based on propensity score matching

This study aimed to compare the efficacy of human chorionic gonadotropin (hCG) and dual-trigger (gonadotropin-releasing hormone agonist [GnRH-a] and hCG) protocols in terms of cumulative live birth rate (CLBR) and other pregnancy outcomes among advanced-age women. We enrolled 801 women aged ≥ 35 years who were experiencing infertility and beginning their first in vitro fertilization cycle at a tertiary academic medical institution between August 2015 and June 2023. Among these, 115 and 686 women used the dual-trigger and hCG methods. Propensity score matching was employed to account for confounding variables. The main outcomes evaluated were CLBR and time to live birth (TTLB). The CLBR did not differ significantly between the hCG and dual-trigger groups (29.86% vs. 26.09%, P = 0.44), whereas the TTLBs of both groups were similar (9.60 vs. 10.14 months, P = 0.72). CLBR results were similar for both groups, according to a Kaplan-Meier analysis (hazard ratio [HR] = 0.95; 95% confidence interval [CI] 0.63-1.43; P = 0.82). After a multiple Cox proportional hazards model was established, the CLBR of the hCG group remained comparable with that of the dual-trigger group (HR = 0.83; 95% CI 0.53-4.11; P = 0.39). The subgroup analysis also showed similar findings. Considering the higher fertilization rate and shorter TTLB, the dual-trigger protocol may be more suitable than the hCG trigger protocol.