Reproductive Immunology refers to a field of medicine that studies the feto-maternal (baby-mother) immunologic relationship and the mechanisms through which this paradoxical communication is regulated via fetal antigen presentation (proteins presented to the mother’s immune system on the surface of embryo cells) and recognition and the response of the maternal immune system to these antigens.

Simply put, the mother’s body needs to successfully adapt towards the immunologically different fetus, developing what is referred to as Active Immunological Tolerance which essentially protects the fetus from a potentially hostile immunological reaction against it and creating an immunologically privileged, baby-friendly uterine environment.

When there is a dysregulation or imbalance in the mother's immune system, it can compromise the successful implantation and endanger the embryo. This can lead to implantation failure, recurrent miscarriages, and other pregnancy complications. It is important to understand and address any immune system dysregulation to optimize the chances of a successful pregnancy outcome.