Extracellular RNA: A new perspective on the human pre-implantation embryos

It is currently a challenge to perform noninvasive molecular biological analysis of in vitro fertilized embryos. In this issue of Cell Genomics, Wu et al.1 developed a non-invasive method to evaluate human pre-implantation embryos by characterizing the extracellular RNAs in spent media from the culture of in vitro fertilization embryos.