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Despite many advances in medically assisted reproduction (MAR), only 10–15% of the embryos replaced result in the birth of a child. Some of the failures are directly attributable to the embryo itself, but the main limiting factor is implantation failure, often associated with desynchronizations of dialog between embryonic and maternal tissue. Over the past decade, Omics techniques (high-throughput techniques) have been widely used in the field of fertility. In particular, the study of circulating nucleic acids (microRNAs, free DNA) has been the subject of important scientific and medical advances. They currently occupy an important place as biomarkers of interest in human pathology, especially in cancer. Easily accessible in biological fluids or in the embryonic culture medium, they are the tools of choice in MAR for the development of new non-invasive diagnostic and prognostic tests. The use of these biomarkers in the assessment of the ovary reserve and embryonic quality, and in the prevention of implantation failures, corresponds to an innovative and extremely promising approach in the field. On the other hand, Omics techniques have enabled major advances in the identification of endometrial receptivity biomarkers, which have in turn led to the establishment of an endometrial receptivity test, prompting practitioners to revisit their practices.