P-777 Comparison of GnRH-a trigger and GnRH-a plus low-dose HCG trigger for high ovarian responders in IVF/ICSI: A retrospective study based on propensity score matching
Authors: Li Y 
Published: August 2021

Abstract

Study question
Does GnRH agonist trigger for high responders during IVF/ICSI cycles improve the number of good-quality embryos, the incidence of moderate-to-severe OHSS, and pregnancy outcome compared to GnRH-a plus low-dose HCG?

Summary answer
GnRH-a trigger alone can effectively reduce the incidence of moderate-to-severe OHSS in women with high ovarian responses without affecting embryo quality.

What is known already
Previous studies have shown conflicting results on the different trigger protocol in high responders in IVF/ICSI outcomes, and as for women with high ovarian response, there is little known about the effects of GnRH-a plus low-dose HCG versus GnRH-a alone on oocytes maturation, the rate of good quality embryos, the incidence of moderate-to-severe OHSS, and pregnancy outcome during IVF/ICSI cycles.

Study design, size, duration
A retrospective analysis was conducted on patients with high ovarian response who received IVF/ICSI treatment with a flexible GnRH antagonist regimen, at the Center of Reproductive Medicine, Chengdu Jinjiang Hospital for Maternal and Child Health Care, from January 1 2017 to December 31 2018. Using 1:1 propensity score matching, 513 cases entered each group (a total of 1,026 females).

Participants/materials, setting, methods
The high responders were included and assigned to groups A (0.2 mg triptorelin) and B (0.2 mg triptorelin plus 2000 IU HCG) for final oocyte maturation. Their basic clinical characteristics, information about controlled ovarian stimulation cycle, embryologic data, and pregnancy outcome in FET were retrospectively compared. The main outcome measures of the study were the rate of good-quality embryos, the number of available embryos, the incidence of moderate-to-severe OHSS, and the cumulative live-birth rate.

Main results and the role of chance
Using 1:1 propensity score matching, 513 females were included in each group. No significant differences in baseline clinical data were found between the two groups, including age at diagnosis, spouse’s age, the duration of infertility, the infertility type, and the cause of infertility, BMI, anti-Müllerian hormone (AMH) levels, and the antral follicle count (AFC) (p &gt; 0.05). None significant differences were found in the total doses of gonadotropin (Gn), the duration of ovarian stimulation, serum P and LH levels on the trigger day, the number of oocytes retrieved, the rate of 2PN embryos, and the rate of good-quality embryos (p &gt; 0.05). The serum E2 level on the trigger day in group A was significantly higher than that in group B (p &lt; 0.001). Women in group A had a lower incidence rate of moderate-to-severe OHSS than individuals in group B (p &lt; 0.001). There was a non-significant difference in the cumulative live-birth rate between the two groups (p &gt; 0.05).

Limitations, reasons for caution
As this is a retrospective study that uses data initially collected for other purposes, limitations may exist in the selection, implementation, and measurement biases that cannot be avoided. However, our study underlies the need for further prospective, multi-center joint-controlled studies to validate these findings.

Wider implications of the findings
This study demonstrates that GnRH-a alone can reduce the incidence of moderate-to-severe OHSS without harming embyro quality in women with high ovarian response. These findings need further prospective validations in hyperresponsive populations by multi-center, large-sample, randomized controlled studies.

Trial registration number
N/A