Severe fetomaternal transfusion due to an unrecognized chorangioma in a dichorionic, diamniotic twin pregnancy

OBJECTIVES/HYPOTHESIS: Severe fetomaternal transfusion due to an unrecognized chorangioma in a dichorionic, diamniotic twin pregnancy: case report and review of the literature. STUDY DESIGN: Case report and retrospective narrative review. METHODS: Evaluation of 8 case reports. CASE REPORT: A 32-year-old primigravida with dichorionic, diamniotic twin pregnancy developed growth discordance and hypertension. At 35 weeks, cesarean delivery revealed one viable twin and one severely anemic twin who died immediately postnatal. Fetomaternal transfusion was suspected, confirmed, and most likely caused by a 6 cm chorangioma. CONCLUSION: Fetomaternal hemorrhage is a serious but underrecognized complication and can be caused of placental chorioangiomas, among other things. Although rare, it poses significant risks of fetal anemia and perinatal morbidity. Increased awareness and routine Doppler monitoring of at-risk fetuses may facilitate earlier diagnosis and timely intervention, potentially improving outcomes. Particularly in children with anemia, fetomaternal transfusion should always be considered and HbF material determined.