Editorial
Wolfgang Würfel
Abstract
The situation is actually clear-cut: an embryo is HLA-foreign for the prospective mother due to its foreign, paternal HLA identity. This difference affects an average of 50% of HLA groups. Logically, then, any pregnancy represents an enormous challenge for the maternalimmune system. HLA typing undisputedly plays an important role in transplantation medicine, and it is now generally known that immune system reactions must be precisely monitored and treatment given where required. However, pregnancy is often regarded different. The view prevailing in areas including reproductive medicine is that it is “all about the embryo” while the embryo’s foreign HLA is ignored. Current reproductive medicine thus focuses on genetic embryo screening aimed at improving pregnancy rates, with no other general trend in sight.