¿What is the Signature of Human Conception?
The Signature of Human Conception is a snapshot at the molecular level that allows the identification of unique patterns of biomarker expression. In this case, initially, protein and peptides - through massive study by mass spectrometry - in the context of the natural development of a pregnancy within the mother's womb. This research begins from the moment of fertilization until the implantation of the embryo in the endometrium.
The research during these last two years has been carried out from a study model where serial samples of cervicovaginal fluid from cohorts of women with conceptional and non-conceptional cycles are compared, this has allowed us to advance in A) the generation and analysis of massive data on differential protein expression, b) delineate markers that characterize the signature of human conception, c) biological pathways or processes that are being modulated behind phenomena such as fertilization, ultra-early embryonic development, preimplantation embryonic maternal dialogue , implantation in the maternal uterus.

The pathways of different biological processes are activated or inhibited in a coordinated way through the maternal recognition of the human embryo and the interaction between the embryo and the maternal endometrium. The concept of signature therefore has to do with the exhaustive description of this unique phenomenon in a finished way.
Research and clinical applications
At the research level we are describing a process that to this day is unknown. There is no direct evidence of what happens in vivo in the dialogue between the human embryo and the mother in the pre-implantation period.
From basic research there are great questions to be investigated from a phenotypic perspective. If we know the protein profile of a sample and its post-translational modifications, we could know how a genetic program is being implemented, particularly the biological pathways that are interacting. This approach is important today, for the search for markers, since we are not studying something as static as DNA, but precisely a process strongly determined by hormonal changes in the menstrual cycle and perhaps also by the presence of gametes, ultimately , the expression in a tissue or fluid in its natural environment of a genetic program that aims to achieve an end: conception.
The description of the Signature would also allow us to establish a map and a roadmap for the ultra-early development of the human embryo before the implantation period. We do not know how many embryos are generated as a result of a fertilizing cycle and how many embryos can be implanted. The Signature could help generate new tools to be able to determine it and to know if, indeed, there could be some affectation in the conception or during the precocious embryonic development or in the same window of endometrial receptivity. It also has applications for the development of ultra-early pregnancy tests, as well as developing markers related to infertility.
