Trophoblast deportation, the removal of trophoblastic debris from the placenta via the
maternal blood, was first described over 100 years ago. Deported trophoblastic debris
ranges in size from nano-meter scale subcellular particles to large multinucleated syncytial
knots. Whether trophoblast deportation has any biological significance remains unclear.
However, the (semi) allogeneic fetus must induce maternal tolerance to paternally inherited
placental antigens. We propose that the clearance of deported trophoblasts may be a …