Placental chorioangioma: a rare cause of fetomaternal transfusion with maternal hemolysis and fetal distress.

Multiple placental chorioangiomas in a 31-year-old woman led to a severe, acute fetal-to-maternal transfusion and maternal hemoglobinuria from hemolysis of the fetal red blood cells. Fetal distress was manifest by a sine wave fetal monitor pattern. A severely asphyxiated infant was delivered by cesarean section. The infant did well after transfusion therapy.