Hemolytic disease of the fetus and newborn (HDFN) is a life-threatening disorder in which maternal alloantibodies destroy fetal and neonatal red blood cells. Current treatment options including intravenous immunoglobin, intrauterine transfusions, and plasmapheresis have reduced mortality, but evidence is lacking for timing and optimal treatment combinations. A large, retrospective, international cohort study analyzed data from 2,420 pregnant women with confirmed maternal alloantibodies to incompatible fetal antigens (excluding ABO antigens, 73% were RhD antibodies) at 31 health care centers (21 in Europe, 4 in North America, 3 in South America, 1 in the Middle East, and 1 each in Africa and Asia). Overall, 4% (95/2420) of pregnancies ended in fetal deaths, and 56% (1349/2420) received some sort of antenatal treatment. The median time to treatment referral for HDFN was 20.4 gestational weeks but varied from 10 to 26 weeks between centers. The median number of intrauterine transfusions per pregnancy was 2 (IQR=1-4); placental sites for transfusion insertion were the most common (60.3%) followed by intrahepatic (20.7%) and free loop (7.5%). Lethal complications due to prenatal transfusions, however, were lower for intrahepatic insertions (2.0%) compared to placental (6.9%) and free loop (13.3%). Notably, the study found that fetal deaths were highest at earlier gestational age, but no deaths were observed when prenatal transfusion occurred at 32.0 gestation age or later. Prospective studies are needed to better understand the optimal treatments and timings for HDFN.
References:
- de Winter, D.P., Lopriore, E., Thorup, E., Petersen, et al. Variations in antenatal management and outcomes in haemolytic disease of the fetus and newborn: an international, retrospective, observational cohort study. The Lancet Haematology; 2024
- J Andrews and MR Grace. Time to optimize management of haemolytic disease of the fetus and newborn. The Lancet Haematology; 2024
