Effects of gonadotropin-releasing hormone antagonist (GnRH-ant) cessation on trigger day in a GnRH-ant protocol: a meta-analysis.

Background: The gonadotropin-releasing hormone antagonist (GnRH-ant) protocol is associated with few oocytes retrieved, few mature oocytes and poor endometrial receptivity. Omission of GnRH-ants on trigger day seems unlikely to induce preovulation and may improve outcomes in the GnRH-ant protocol. This study aimed to systematically evaluate the effects of GnRH-ant cessation on trigger day on in vitro fertilisation outcomes following the GnRH-ant protocol.

Methods: We searched PubMed, Ovid/MEDLINE, Wanfang, VIP, CNKI and ClinicalTrials.gov databases. The last search was conducted on 10 December 2023 in English or Chinese, without time limitations on the collection of studies from the databases. The references in these articles were manually searched. Randomised controlled trials (RCTs) and cohort studies aimed at assessing the effects of GnRH-ant cessation on trigger day using the GnRH-ant protocol were included. The eligible studies included at least one of the main outcomes: number of oocytes retrieved, proportion of mature oocytes, implantation rate or clinical pregnancy rate.

Results: Three studies with 1449 cycles were included. Cessation of GnRH-ant on trigger day improved the proportion of mature oocytes (odds ratio [OR] = 1.26, 95% confidence interval [CI] = 1.09-1.45, = 0%) but did not affect the number of oocytes retrieved (mean difference [MD] = 0.50, 95% CI = -0.07 to 1.07, = 47%), implantation rate (OR = 0.95, 95% CI = 0.69-1.30, = 0%), clinical pregnancy rate (OR = 1.06, 95% CI = 0.71-1.58, = 0%), endometrial thickness (MD = -0.09, 95% CI = -0.27 to 0.10, = 0%) or cycle cancellation rate (OR = 0.64, 95% CI = 0.15-2.74, I = 0%).

Conclusions: Cessation of GnRH-ant on trigger day of the GnRH-ant protocol is suggested because it could improve the proportion of mature oocytes. However, further RCTs are required.