Some severe maternal diseases might be caused by fetal-versus-maternal disease (FVMD).

Pregnancy-related disease is a common challenging clinical problem. From our review and clinical experience, we hypothesize that many severe pregnancy-related complications might be caused by a fetal-versus-maternal disease (FVMD), based on the fact that maternal disease is related to immunity and that fetal cells are present in maternal blood. Fetus is a semi-antigen and can be considered as a tumor or graft. The pathophysiology of FVMD must be complex. We speculate it to be a three-step process: impaired maternal immunological function, fetal T-cell activation and injury of target organs. More experiments and research will be needed to prove our hypothesis.