Source:http://linkedlifedata.com/resource/umls/id/C0035404
MSH: The process by which fetal Rh+ erythrocytes enter the circulation of an Rh- mother, causing her to produce IMMUNOGLOBULIN G antibodies, which can cross the placenta and destroy the erythrocytes of Rh+ fetuses. Rh isoimmunization can also be caused by BLOOD TRANSFUSION with mismatched blood.