A comprehensive characterization of cell-free RNA in spent blastocyst medium and quality prediction for blastocyst

New approaches in the analysis of spent embryo culture media in the IVF process

PURPOSE

In vitro fertilization occurs in a controlled laboratory setting, where oocytes are fertilized by sperm, and the resulting embryos are cultured to the blastocyst stage before transfer to the uterus. The secreted/consumed substances by the embryo in the extracellular environment (secretome) contain a variety of molecules that may provide insights into embryo quality. This study presents new perspectives on the non-invasive and cost-effective assessment and evaluation of embryos during the IVF process, utilizing a spent embryo culture medium (SECM).

METHODS

The SECM was used from blastocysts prepared for a single blastocyst transfer and was analyzed in two groups-the SECM with successful (F) (n = 30) and unsuccessful (N) (n = 36) embryo implantation in the woman's uterus. Building on our previous next-generation sequencing results, we decided to validate the expression levels of specific miRNAs, particularly hsa-miR-16-5p and hsa-miR-92a-3p, to assess their potential to predict embryo implantation success.

RESULTS

Our results demonstrate different expression levels of miRNA molecules in the monitored groups, which could lead to their use in non-invasive analysis of the implantation potential of embryos in the IVF process. In this study, we employed a metabolomics approach using 3D fluorescence analysis of SECM to identify differences between the studied groups, F and N. Our preliminary results indicate a slightly increased metabolic activity in the group with unsuccessful embryo implantation group.

CONCLUSIONS

This is our pilot study where we demonstrated the use of two approaches in analyzing the SECM to predict the implantation potential of embryos in the IVF process which promises further development.

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.