A Novel Stimulation Protocol for Poor-Responder Patients: Combining the Stop GnRH-ag Protocol with Letrozole Priming and Multiple-Dose GnRH-ant: A Proof of Concept

Objective The objective of this study was to examine whether the combined Stop GnRH-agonist (GnRH-ag), letrozole priming, and multiple-dose GnRH-antagonist (GnRH-ant) protocol may improve in vitro fertilization/intracytoplasmic sperm injection cycle in poor ovarian responders (PORs). Design This was a historical cohort, proof of concept study under tertiary setting at University affiliated Medical Center. Patients Five PORs fulfilling the POSEIDON Group 4 criteria were included. Main outcome measures Number of oocytes retrieved, number of top-quality embryos (TQEs), and controlled ovarian hyperstimulation (COH) variables were the main outcome measures. Results The combined Stop GnRH-ag, letrozole priming, and multiple-dose GnRH-ant COH protocol revealed significantly higher number of follicles >13 mm on the day of hCG administration and higher number of oocytes retrieved, with non-significantly more TQEs and a reasonable clinical pregnancy rate. Conclusions The combined Stop GnRH-ag, letrozole priming, and multiple-dose GnRH-ant COH protocol is a valuable tool in the armamentarium for treating POSEIDON Group 4 patients. Further large prospective studies are needed to elucidate its role in POR and to identify the specific characteristics of women (before initiating ovarian stimulation) that will aid both fertility specialists' counseling and their patients in adjusting the appropriate COH protocol.