Embryo secretome in predicting embryo quality and IVF treatment outcome

In IVF treatment, accurate prediction of embryo quality and successful embryo implantation are critical challenges. Recent research has highlighted the importance of the embryo secretome, the collection of molecules secreted by the embryo into the culture medium, in assessing embryo quality as a non-invasive preimplantation testing platform. The secretome plays a role in many essential processes, from gamete maturation to embryonic development. Molecules such as cell-free DNA, mitochondrial DNA and small non-coding RNA, including microRNA and PIWI-interacting RNA, together with the proteome, metabolome, microbiome and extracellular vesicles, have emerged as important players in predicting IVF outcomes. These molecules, present in the culture medium, have shown correlations with embryo viability, ploidy and implantation potential. Nevertheless, extensive validation in larger cohorts and an assessment of the applicability of the identified biomarkers in clinical settings is warranted. This article summarizes the molecular markers analysed in spent embryo culture medium and their potential for assessing embryo quality and predicting success in IVF outcomes.