Hydrops Fetalis

What is hydrops fetalis?

Hydrops fetalis is severe swelling (edema) in an unborn baby or a newborn baby. It is a life-threatening problem. There are 2 types: immune and nonimmune.

What causes hydrops fetalis?

Immune hydrops

This type of hydrops is not very common. It may develop because of Rh disease in the mother. If you are Rh negative and have an Rh positive baby, your immune system attacks your unborn baby’s red blood cells. This causes anemia. Hydrops can occur if the developing baby's organs can't overcome the anemia. The heart starts to fail. Large amounts of fluid build up in the baby's tissues and organs. This type of hydrops is not common today because Rh negative women are usually treated with Rh immunoglobulin to prevent this problem.

Nonimmune hydrops

This is the more common type of hydrops. This type includes all other diseases or complications that may interfere with how your baby manages fluid. Some of the diseases or conditions that can cause nonimmune hydrops include:

  • Severe anemia
  • Infections present before birth
  • Heart or lung defects
  • Chromosomal abnormalities and birth defects
  • Liver disease

What are the symptoms of hydrops fetalis?

Symptoms can occur a bit differently in each child. Below are the most common symptoms of hydrops.

During pregnancy, symptoms may include:

  • Large amounts of amniotic fluid
  • Thickened placenta
  • Ultrasound of the unborn baby that shows enlarged liver, spleen, or heart. It may show a fluid buildup around the baby’s abdominal organs, heart, or lungs.

After birth, symptoms may include:

  • Pale coloring
  • Severe swelling overall, especially in the baby's belly (abdomen)
  • Trouble breathing
  • Enlarged liver and spleen

The symptoms of hydrops may look like other health conditions. It is almost always diagnosed during pregnancy or immediately at birth.

How is hydrops fetalis diagnosed?

Before birth your baby may need these tests:

  • Ultrasound.This test uses sound waves to create images of blood vessels, tissues, and organs. The healthcare provider will use the ultrasound to look at how your baby's internal organs are working. The provider can see how blood flows through different vessels.
  • Fetal blood sampling. This is done by placing a needle through your uterus and into 1 of your baby’s blood vessels or the umbilical cord.
  • Amniocentesis. This test is done by removing some of the amniotic fluid around your baby for testing.

How is hydrops fetalis treated?

Treatment of hydrops depends on the cause. During pregnancy, hydrops may be treatable only in certain cases. You may need to deliver your baby early. In a newborn baby, treatment may include:

  • Help for breathing problems. This may be with extra oxygen or a breathing machine (ventilator)
  • Removing extra fluid from spaces around the lungs, heart, or inside the belly using a needle

What are possible complications of hydrops fetalis?

The severe swelling that occurs with hydrops can overwhelm the baby's organ systems. About 50% of unborn babies with hydrops don’t survive. Risks for other problems are also high for babies born with hydrops. Survival often depends on the cause and treatment.

Key points about hydrops fetalis

  • Hydrops fetalis is severe swelling (edema) in an unborn baby or a newborn baby. It is a life-threatening problem.
  • Hydrops develops when too much fluid leaves the baby's bloodstream and goes into the tissues.
  • Treatment of hydrops depends on the cause.
  • About 50% of unborn babies with hydrops don’t survive.
Want More Information?

Cedars-Sinai has a range of comprehensive treatment options.

Looking for a Physician?

Choose a doctor and schedule an appointment.

Need Help?


Available 24 Hours A Day