Background and Objective: The endometrium and embryos have been reported to be directly affected by GnRH agonists (GnRHa). Additionally, as demonstrated by numerous meta-analyses, the utilization of GnRHa during the luteal phase of fresh IVF cycles has been correlated with an increase in the rates of live birth and pregnancy. This study aimed to ascertain whether GnRHa administration during the luteal phase could enhance the results of in vitro fertilization (IVF) in patients who are undergoing frozen embryo transfer (FET) cycles.
Materials and Methods: In order to prepare the endometrium, hormone replacement therapy (HRT) was implemented in a total of 166 frozen embryo transfer cycles during this randomized controlled trial. The cycles were divided into two equal groups, each consisting of 83 cycles. Two hours after the embryo transfer, a single subcutaneous dose of 0.2 mg triptorelin (Decapeptyl) was administered to the GnRHa group. Devoid of the administration of luteal GnRHa, the control group underwent embryo transfer. In this study, the clinical pregnancy rate was the primary outcome, while the ongoing pregnancy rate was the secondary outcome.
Results: Both groups exhibited remarkable similarities in their baseline and cycle characteristics. The luteal GnRHa group has a clinical pregnancy rate that was significantly higher than those of the control group (57.8% vs. 41.0%, P = 0.030). Rates of ongoing pregnancy were comparable in both groups (41.0% vs. 25.3%; P = 0.476). Furthermore, the use of a luteal GnRH agonist was identified as a significant independent predictor of clinical pregnancy in FET-HRT cycles, as indicated by the multivariate analysis (OR 1.512, 95% CI 1.020-2.241, P = 0.039).
Conclusions: The clinical pregnancy rates of patients who are undergoing the HRT-FET protocol may be enhanced by addition of a single luteal dose of GnRHa.