Sonographic findings in severe fetomaternal transfusion

Fetomaternal hemorrhage (FMH) or fetomaternal transfusion syndrome is the leakage of fetal red blood cells into the maternal circulation. Massive FMH can cause substantial fetal morbidity and mortality. Sonographic evidence of severe FMH syndrome includes fetal hydrops and other fetal anemia-related findings. The peak systolic velocity in the middle cerebral artery has extensively been used for the prediction of fetal anemia and for the timing of the first intrauterine intravascular transfusion (IIVT). We present a case of severe FMH syndrome that was diagnosed during the 24th week of pregnancy. A total of eight IIVT were performed. The actual increase in the fetal Hb after each transfusion was much lower than the expected. At 27 weeks of gestation, sonographic evaluation revealed areas of echogenicity around the posterior horns of the lateral ventricles suggesting ischemic damage. Due to these findings, no further IIVTs were offered and the fetus died a week later. The management of fetal anemia caused by severe FMH is difficult, and the anemic fetuses do not respond well to serial IIVTs as the transfer of blood to the maternal circulation continues.