Abstract
Recurrent implantation failure (RIF) is one of the core problems for assisted reproductive technology (ART). High-quality, euploid embryos and synchronization between the embryonic stage and the uterine endometrial lining are crucial for positive outcomes. Molecular biology techniques have significantly transformed assisted reproductive technology (ART). Numerous couples facing infertility issues have successfully achieved the birth of healthy infants through the application of molecular biology methods: preimplantation genetic testing for aneuploidy (PGT-A) and endometrial receptivity analysis (ERA). Exploring the impact of age on endometrial assays like the endometrial receptivity assay (ERA) yields valuable insights, including the determination of the implantation window and the development of personalized strategies. The authors present the case of a 42-year-old woman who has experienced RIF with euploid embryos, coupled with a hereditary thrombophilia homozygous mutation in the MTHFR genes: A1298C and C677T.