What is HDFN?
Hemolytic disease of the fetus and newborn (HDFN) is a blood disorder in which a pregnant person’s immune system produces antibodies that cross the placenta and destroy the red blood cells of the fetus or newborn, leading to hemolysis, anemia, jaundice or possibly fetal death. With close monitoring and timely treatment, babies with HDFN have a very high survival rate. Unfortunately, due to the rarity of alloimmunization and the variation in care practices around the world, well-managed pregnancies and ideal infant outcomes are not universal.
HDFN can occur when the mother and baby have incompatible blood types, most commonly involving the Rh factor or other blood group antigens such as Kell. As red blood cells are destroyed, the fetus can develop anemia and other complications. Early detection and treatment significantly improve outcomes.
What causes HDFN?
HDFN develops when maternal antibodies cross the placenta and destroy fetal red blood cells. This immune response may develop after exposure to fetal blood cells during a previous pregnancy, miscarriage, delivery, blood transfusion or other pregnancy-related events.
Many women do not experience noticeable symptoms. The condition is often identified through routine prenatal screening. Healthcare providers may detect maternal antibodies, fetal anemia, enlarged fetal organs, excess amniotic fluid or hydrops fetalis.
Affected babies may develop anemia, jaundice, pale skin, rapid heart rate, enlarged liver or spleen, swelling from fluid buildup, breathing difficulties or severe jaundice requiring urgent treatment.
Diagnosis typically includes maternal blood typing, Rh factor testing, antibody screening, follow-up antibody testing, ultrasound examinations and Doppler ultrasound monitoring to assess fetal anemia.
Women with clinically significant antibodies may require referral to a maternal-fetal medicine specialist, additional prenatal monitoring, regular ultrasounds, blood testing and fetal surveillance. Severe fetal anemia may require an intrauterine transfusion. In some cases, early delivery may be recommended.
Newborns may require bilirubin monitoring, phototherapy, blood transfusions, neonatal intensive care and ongoing follow-up for anemia and other complications.
Contact your healthcare provider promptly if you have been told you have red blood cell antibodies, are Rh-negative and have concerns about incompatibility, notice decreased fetal movement, or have concerns about your pregnancy. After delivery, seek immediate medical attention if your newborn develops jaundice, poor feeding, unusual sleepiness, breathing difficulties, pallor or swelling.
Many cases of Rh(D)-related HDFN can be prevented through Rh immunoglobulin (RhIg) administration in eligible Rh-negative mothers, along with routine prenatal screening and monitoring.
To learn more about HDFN, please visit our partners at Allo Hope Foundation (AHF) (www.allohopefoundation.org). Whether you've recently received a diagnosis, are expecting a baby, planning for postpartum care or caring for patients, AHF offers resources and support to help guide you every step of the way.
The history of HDFN: History of HDFN - Allo Hope Foundation
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