Live birth rate following endometrial preparation with daily versus depot GnRH agonist

Background Gonadotrophin-releasing hormone agonist (GnRHa) downregulates gonadotropin secretion in the pituitary gland. It is used both in ovulation induction protocols and in artificial endometrium preparation. Frozen-thawed embryo transfer to artificially prepared endometrium (FET-APE) is a frequent procedure in vitro fertilization (IVF) which requires GnRHa. It can be used either as a daily low-dose injection or as a single depot injection. It is unclear which of these two regimens is superior for artificial endometrium preparation.Methods We evaluated the data of 72 patients who had undergone frozen embryo transfer following the 5th day Preimplantation Genetic Test-aneuploidy (PGT-A) between 2018-2021. All embryos were genetically screened, and euploid single embryos were transferred. Group 1 (n: 36) used depot GnRHa, and Group 2 (n: 36) used single daily injections for artificial endometrial preparation. The outcomes for Beta Human Chorionic Gonadotrophin (BHCG) positivity and live birth rates (LBR) was compared.Results The BHCG positivity for Group 1 and Group 2 was 75% and 80.6%, respectively. The LBR for Group 1 and Group 2 were found to be 58.3% and 63.9%, respectively. There was no statistically significant differences between the two groups.Conclusions In artificial endometrium preparation, depot GnRHa offers cheaper and more convenient alternative to single daily dose injections, particularly in busy clinical settings. Gonadotrophin-releasing hormone agonist (GnRHa) is used to Frozen-thawed embryo transfer to artificially prepared endometrium (FET-APE). However, it is not known which of the depot and daily preparations is more effective. Our study to exclusively compare 5th day euploid single embryos transferred in FET-APE cycles using depot or daily injections of GnRHa to avoid any influences of oocyte or spermatozoa dependent factors on Beta Human Chorionic Gonadotrophin (BHCG) positivity and live birth rates (LBR). The results were similar. Since the results are similar, the depot GnRHa form can be preferred for ease of use. However, future studies on larger series and patients with different clinical characteristics may effects the results.