Infertility concerns 1 out 6 couples wishing to conceive and the worldwide use of assisted reproduction technology (ART) increases by 5 to 10% each year. Nevertheless, 10-20% of infertilities remain idiopathic. Understanding the window of human embryo peri-implantation development is essential to appreciate the beginning of human life but also for multiple clinical approaches such as in vitro fertilization, regenerative medicine and placenta physiopathology.

 

            Therefore, in order to investigate the mysteries of human embryo peri-implantation development and go beyond transcriptomic analysis, we studied the proteome of human embryos at different stages of development using a last generation DIA mass spectrometry approach. MS analyses were performed on pre-human implantation embryos at the morula, pre-implantation blastocyst stages, and human embryos miming the post-implantation blastocyst stage at days 8 and 10. It allowed the identification of 3,070 to 4,389 proteins depending on the stage of development. We could characterize several significant changes during the human embryo peri-implantation development., with some proteins displaying a progressive modification in their expression, while others suddenly appeared or disappeared at a specific stage. Interestingly, the profile of proteins involved in metabolism depends on the embryo stage, highlighting the different requirements of the human embryo during pre, peri and post implantation development.

 

            Our original work lead to the first proteome of the human embryo peri-implantation development including post-implantation embryo. It opens up new horizons for research not only on the human embryo, but also on stem cells and on the blastoid (pre-implantation blastocyst organoid) model. Altogether, these models could contribute to improve IVF success rate