A long-term gonadotropin-releasing hormone agonist protocol may be associated with increased positive pregnancy outcomes in women with endometriosis undergoing frozen embryo transfer
1. Long-term gonadotropin-releasing hormone agonist (GnRH-a) protocol was associated with higher odds of positive pregnancy outcomes for women with endometriosis undergoing frozen embryo transfer (FET), compared with GnRH-antagonist (GnRH-ant), and mild-ovarian stimulation protocols.
Evidence Rating Level: 2 (Good)
In vitro fertilization (IVF) is one of the most effective treatments for infertility associated with endometriosis. A key component of IVF is ovarian stimulation. Previous studies have compared the effectiveness of various ovarian stimulation protocols for fresh embryo transfer in women with endometriosis; however, the effectiveness of these protocols for frozen embryo transfer (FET) is unclear. This study thus examined the efficacy of three different controlled ovarian stimulation (COS) protocols: long-term gonadotropin-releasing hormone agonist (GnRH-a), GnRH-antagonist (GnRH-ant), and mild ovarian stimulation, in endometriosis patients undergoing FET. This retrospective study included women (<40 years) with stage III–IV endometriosis who received one of the three COS protocols during January 1, 2015, to December 31, 2022. The primary outcome was live birth rate. Among the 636 patients included, 118 received GnRH-a, 295 received GnRH-ant, and 223 received mild-ovarian stimulation protocols. Compared to the GnRH-a group, the GnRH-ant group had lower odds of live birth (odds ratio [OR] 0.62, 95% confidence interval [CI] 0.47–0.83), whereas the mild-ovarian stimulation group had no significant difference in odds of live birth (OR 0.87, 95% CI 0.65–1.16). Compared to the GnRH-a group, both GnRH-ant and mild-ovarian stimulation groups had a lower rate of high morphological grade embryos (GnRH-ant: OR 0.73, 95% CI 0.55–0.98; mild: OR 0.69, 95% CI 0.51–0.94) and lower biochemical pregnancy rate (GnRH-ant: OR 0.62, 95% CI 0.47–0.83; mild: OR 0.73, 95% CI 0.54–0.98). Overall, this study found that compared to GnRH-ant and mild-ovarian stimulation protocols, the GnRH-a protocol was associated with higher odds of positive pregnancy outcomes for women with endometriosis undergoing FET. These findings suggest that the GnRH-a protocol may be a more effective ovarian stimulation option for this population, and the mild-ovarian stimulation protocol may serve as an alternative when considering only live birth rate.
Click here to read this study in the European Journal of Medical Research
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