Effect of dual trigger on reproductive outcome in low responders: a systematic PRISMA review and meta-analysis

Objective: Poor ovarian responders (PORs) pose a great challenge for fertility clinics worldwide. The aim of this study was to examine whether ‘dual trigger’ consisting of human chorionic gonadotropin (hCG) plus gonadotropin-releasing hormone agonist (GnRHa) is beneficial or not regarding implantation rate, pregnancy rate, and live birth rate for POR. Methods: This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement. Risk of bias was evaluated by the Newcastle–Ottawa scale or version 2 (NOS) of the Cochrane risk-of-bias tool for randomized trials (ROB2) independently by two authors. Furthermore, RevMan version 5.4 was used to analyze the extracted data and to create an inverse-weighted summary-odds ratio (OR). Results: A total of 1390 studies were screened. Seven studies containing a total of 2474 POR were included. The pooled meta-analysis revealed a 1.62-fold increase in clinical pregnancy rate (OR = 1.62 [1.00, 2.62], p =.05) and a 2.65-fold increase in live birth rate (OR = 2.65 [1.66, 4.24], p <.0001) in the dual trigger group compared to hCG trigger. The pooled analysis showed no significant difference between the two groups regarding implantation rate (OR = 1.14 [0.93, 1.39], p =.21). Conclusions: The meta-analysis of this study indicates that dual trigger as finale oocyte maturation is advantageous compared to hCG trigger among POR. However, large-scale, high-quality, randomized controlled trials (RCT) are required to confirm this conclusion and fully address the magnitude of this effect.