Pregnancy outcome in delayed start antagonist versus microdose flare GnRH agonist protocol in poor responders undergoing IVF/ICSI: An RCT

Over the years, many article on different aspects of pathogenesis and management of poor ovarian responders have been published but there is no clear guideline for treating themyet.

This study was designated to compare the effectiveness of a delayed start protocol with gonadotropin-releasing hormone (GnRH) antagonist and microdose flare-up GnRH agonist protocol in poor ovarian responders.

This randomized clinical trial consisted of 100 poor ovarian responder women in assisted reproductive technologies cycles. They were divided randomly in delayed-start antagonist protocol (with estrogen priming followed by early follicular-phase GnRH antagonist treatment for 7 days before ovarian stimulation) and microdose flare-up GnRH agonist protocol. The main outcome was clinical pregnancy rate and second outcome was the number of retrieved oocytes, mature oocytes, 2PN number, fertilization rate, and implantation rate.

Fertilization rate, clinical pregnancy rate, and ongoing pregnancy rates were not significantly different between the two studied protocols. Number of retrieved oocytes (5.10±3.41 vs. 3.08±2.51) with p=0.002, mature oocytes (4.32±2.69 vs. 2.34±1.80) with p=0.003, number of 2PN (3.94±1.80 vs. 2.20±1.01) with p=0.001 and implantation rate (19.40% vs. 10.30%) with p=0.022 were significantly higher in delayed antagonist group.

The delayed-start protocol can improve ovarian response in poor responders by stimulating and synchronizing follicle development.