Learn The BasicsThe symptoms of hemolytic disease of the fetus and newborn (HDFN) can be different during each pregnancy, depending on the health of both the mother and baby. Below is a breakdown of the symptoms of HDFN before and after birth as well as the risks and complications.
Symptoms during pregnancy
Usually, a mother who has a baby affected by HDFN will not notice any symptoms during her pregnancy. However, if her doctor performs prenatal testing, the amniotic fluid may have a yellow appearance due to bilirubin, the substance that forms as a result of the breakdown of red blood cells. This is because the mother’s immune system attacks the red blood cells of her baby due to a mismatch between their blood proteins.
The fetus may also have an enlarged liver, spleen or heart and accumulate extra fluid in their stomach, lungs or scalp. This is a condition known as hydrops fetalis, which can be detected before birth.
Symptoms after birth
The symptoms of HDFN in a newborn include:
- Pale skin due to anemia or low red blood cell counts.
- Jaundice or yellowing of the skin or eyes, which may develop 24 to 36 hours after birth.
- Very dark urine.
- Enlarged liver and spleen.
- Severe swelling in the whole body.
HDFN does not cause any symptoms, risks or complications for the mother, either before or after birth.
Risks and complications for the baby
There may be several complications associated with HDFN in an infant or fetus. The most common ones include heart failure due to anemia, hydrops and a condition known as kernicterus.
Heart failure
In severe cases and without proper treatment, anemia caused by HDFN can lead to heart failure in the baby due to the body’s need for more blood. As the heart tries unsuccessfully to keep up with the oxygen demands of the baby’s body, the heart muscle becomes dysfunctional, resulting in edema and fluid accumulation due to increases in pressure.
Hydrops
Fluid accumulation in at least two areas—such as the heart, lungs, abdomen or under the skin—is called hydrops. If not treated, the excess fluid can cause damage to the vital organs and put the baby’s life at risk.
Kernicterus
Bilirubin, which forms as a result of red blood cell breakdown, is lipid soluble and can cross the blood-brain barrier and accumulate in the brain—mainly the basal ganglia—causing irreversible neurological damage. This is called kernicterus or bilirubin encephalopathy.
Bilirubin levels greater than 25 mg/dL increase the risk of kernicterus, the symptoms of which include lethargy, poor feeding, respiratory distress and decreased deep-tendon reflexes.
The symptoms of kernicterus may look like those of sepsis, asphyxia, low blood sugar and intracranial hemorrhage, which is bleeding within the brain.
Reviewed by Harshi Dhingra, M.D., on September 30, 2023.
