• congenital anomalies;
  • fetus;
  • hemolytic disease of the neonate;
  • hydrops fetalis;
  • red blood cell alloimmunization;
  • ultrasound



To assess sonographically brain anatomy in fetuses with severe anemia due to red blood cell alloimmunization undergoing intrauterine intravascular transfusions.


Multiplanar neurosonography was performed in seven consecutive hydropic fetuses undergoing intrauterine transfusions (mean gestational age 22 ± 2.5 weeks; mean hemoglobin concentration at the first transfusion 2.3 ± 1.0 g/dL).


Abnormal cerebral findings were identified in four out of seven fetuses. An intracerebellar hemorrhage developed in two fetuses after the first transfusion and one fetus that had severe brain edema before the first transfusion was later found to have cystic periventricular leukomalacia. In one fetus unilateral ventriculomegaly was noted after the first transfusion. Two fetuses were terminated. The remaining pregnancies had an uneventful course, the infants were delivered between 34 and 36 gestational weeks and were alive and well at the time of writing. Prenatal diagnosis of brain injury was always confirmed except for the case with ventriculomegaly that underwent spontaneous intrauterine resolution.


Fetuses with extreme anemia due to red blood cell alloimmunization can be salvaged by intrauterine transfusion. In some of these cases brain injury may occur prenatally, and the risk seems to be particularly high when the hemoglobin concentration at the time of the first transfusion is ≤ 2 g/dL. We suggest that in these pregnancies detailed fetal neuroimaging by either multiplanar sonography and/or magnetic resonance imaging is indicated. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.