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.