A case of monochorionic twin pregnancy complicated with intrauterine single fetal death with successful treatment of intrauterine blood transfusion in the surviving fetus.

We report a case of monochorionic twin pregnancy complicated with single fetal demise that received successful treatment of intrauterine transfusion for severe anemia of the surviving fetus. A single fetal demise occurred at 20 weeks of gestation and middle cerebral artery peak systolic velocity (MCA-PSV), a marker for fetal anemia, showed marked elevation in the surviving fetus. Fetal blood sampling was immediately done and severe fetal anemia (hemoglobin = 5.5 g/dl, hematocrit = 16.8%) was confirmed, and then intrauterine transfusion was performed. After transfusion, MCA-PSV rapidly decreased to the normal value and remained within normal range until delivery. A healthy 2,640 g male infant was delivered at 35 weeks of gestation without anemic status and no neurological problem was found at 1-year old. The present report supports that intrauterine rescue transfusion is a useful treatment to prevent the adverse outcome of surviving fetus in monochorionic twin pregnancy complicated with single fetal demise, and monitoring of MCA-PSV is also useful to assess anemic status of the surviving fetus.