Acute Rh isoimmunization following abdominal trauma associated with late abruption placenta.

Acute exacerbation of Rh isoimmunization following abdominal trauma is a rare complication of pregnancy. The report describes a case of a mild case of erythroblastosis fetalis following maternal exposure to massive fetal-maternal transfusion, occurring after abdominal injury in motoring accident. Abruptio placenta 7 days following the trauma indicated emergency cesarean section, at which a severely affected fetus (erythroblastosis fetalis) was delivered. Late abruption--in the presence of no other risk factor--is considered to call for prolonged surveillance. Any abdominal trauma in a Rh-negative woman should alert one to the possibility of massive transplacental hemorrhage and augmentation of the maternal immune response.