Efficacy and Reproductive Outcomes of Combined Versus Single Trigger Protocols in Assisted Reproductive Technology: A Meta-Analytical Study

Ovulation triggering is a critical component of assisted reproductive technology (ART), as the final maturation of retrieved oocytes directly influences subsequent fertilization, embryo development, implantation, and reproductive outcomes. Conventional single-trigger protocols using human chorionic gonadotropin (hCG) have been widely applied, whereas combined or dual-trigger approaches incorporating a gonadotropin-releasing hormone (GnRH) agonist with hCG have been investigated as a strategy to reproduce more closely the physiological hormonal events associated with final follicular maturation. This study synthesizes the evidence provided in six studies examining dual versus single ovulation-trigger approaches in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), with particular attention to reproductive outcomes, ovarian response, live birth, and outcomes in women with diminished ovarian reserve or low response. The methodological approach is based on structured comparative synthesis of the supplied systematic reviews, meta-analyses, retrospective cohort evidence, and comparative clinical studies. The literature generally indicates that dual-trigger protocols may provide clinically meaningful advantages for selected patient populations, although the magnitude and consistency of benefit vary according to ovarian reserve, responder status, treatment characteristics, and outcome definitions. Evidence concerning live birth is particularly important because improvements in intermediate outcomes do not necessarily translate into superior cumulative reproductive success. The analysis highlights the potential value of individualized trigger selection while emphasizing heterogeneity, retrospective evidence, and limitations in direct comparability among studies.