One of the main symptoms of hemolytic disease of the fetus and newborn (HDFN) is anemia. During pregnancy, if HDFN is untreated or progresses to a severe form, anemia can worsen and lead to immune hydrops fetalis. This is the most dangerous complication related to HDFN and has high rates of mortality.
HDFN occurs when a pregnant mother produces antibodies that attack her baby’s red blood cells, and is often the result of a mismatch of blood types or factors between mother and baby, such as Rhd or ABO incompatibility. Pregnant women at risk of having a baby affected by HDFN are often given injections of RhD immunoglobulin designed to prevent the onset of HDFN. They are then carefully monitored throughout their pregnancy.
If HDFN does occur, early detection and treatment of your baby in utero can prevent life-threatening complications such as hydrops fetalis.
Learn more about HDFN symptoms and risks
What is hydrops fetalis?
During pregnancy, if a baby has been diagnosed with HDFN, the baby’s red blood cell count is likely low, meaning oxygen is not being carried from the lungs to cells and organs in the body. This puts pressure on the baby’s heart, and fluid accumulates in the baby’s body, causing it to swell. This is known as immune hydrops fetalis or fetal hydrops. It is relatively rare but can be life-threatening.
Hydrops fetalis is diagnosed via ultrasound, fetal blood sampling and amniocentesis. Following diagnosis, patients may be transferred to a hospital that specializes in the treatment of HDFN and immune hydrops fetalis.
Hydrops fetalis treatment
Prompt treatment is recommended for infants with hydrops fetalis. Treatment options include thoraco-amniotic drainage, antiarrhythmic drugs to treat fetal arrhythmia and fetal blood transfusion. Early delivery of a baby may be required to continue to treat this serious condition. In some cases, a cesarean section may be performed.
Post-delivery, the newborn will require further treatment, such as phototherapy, a ventilator for breathing difficulties, blood transfusion, exchange transfusion, an intervention to reduce fluid around the lungs using a needle and medication to control heart and kidney failure.
Outcomes of hydrops fetalis
Neonatal outcomes are better if hydrops fetalis is resolved before birth or if it develops after 32 weeks’ gestation. However, in severe cases, hydrops fetalis can result in stillbirth or death of the newborn soon after delivery.
Outcomes vary depending on various factors such as gestational age at diagnosis, the severity of the disease and time and frequency of treatment.
