Intrauterine transfusion for fetal anemia due to red blood cell alloimmunization: 14 years experience in Leuven

Objective: The purpose of this study is to report on the pregnancy and neonatal outcome of intrauterine transfusion (IUT) for red blood cell (RBC-)alloimmunization. Material and Methods: Retrospective cohort study of all IUT for RBC-alloimmunization in the University Hospital of Leuven, between January 2000 and January 2014. The influence of hydrops, gestational age and technique of transfusion on procedure related adverse events were examined. Results: 135 IUTs were performed in 56 fetuses. In none of the cases fetal or neonatal death occurred. Mild adverse events were noted in 10% of IUTs, whereas severe adverse events occurred in 1.5%. Hydrops and transfusion in a free loop were associated with an increased risk of adverse events whereas gestational age (GA) at transfusion after 34 weeks was not. Median GA at birth was 35.6 weeks and 9% was born before 34 weeks. Besides phototherapy 65.4% required additional neonatal treatment for alloimmune anemia. Non-hematologic complications occurred in 23.6% and were mainly related to preterm birth. Conclusion: In experienced hands, IUT for RBC-alloimmunization is a safe procedure in this era. Patients should be referred to specialist centers prior to the development of hydrops. IUT in a free loop of cord and unnecessary preterm birth are best avoided.