What Is a Cystic Hygroma?

A cystic hygroma is a rare type of cyst that babies can get, usually in their head or neck, if their lymphatic system gets blocked while it’s developing. (This system helps filter out harmful things, including germs.) Doctors often find cystic hygromas before a baby is born.

Only one in 8,000 babies is born with this kind of cyst. Some of them may also have certain birth defects. So if your baby has a cystic hygroma, your doctor will probably recommend tests to check for that. But some babies born with a cystic hygroma are healthy.

Sometimes these cysts go away on their own. If not, it’s important to get surgery to remove a cystic hygroma so that it doesn’t harm nearby areas of the body, become infected, or make your baby uncomfortable as he or she grows.


Both a baby’s genes and its environment in the womb can make its lymphatic system not grow the right way, letting the cystic hygroma form. It may happen on its own or with genetic conditions such as Turner, Down, or Noonan syndromes.

When adults get a cystic hygroma, it can be due to trauma or a past respiratory infection. But it’s often not clear what caused the cyst. It may even disappear during pregnancy.


Symptoms of a cystic hygroma depend on where and how big it is. The growth may make it hard for nearby organs and other body parts to work the way they should.

In newborn babies, a cystic hygroma looks like a bulge under the skin, which may be slightly blue. Babies born with this type of cyst often have a hard time eating and may grow more slowly than those without cystic hygromas. If a cystic hygroma is near the throat, your baby may have trouble breathing. These cysts can become infected. Left untreated, the cystic hygroma can harm nearby bones and teeth.

The cystic hygroma will get bigger as your baby grows, and it may grow quickly if the cyst becomes infected or there is bleeding inside it.



When you’re pregnant, your doctor may find your baby’s cystic hygroma during a routine ultrasound. (These cysts are usually found by the 20th week of pregnancy.) You may also notice it after your baby is born or even later in your child’s life.

If you find out while you’re pregnant that your baby has a cystic hygroma, your doctor will likely plan for you to give birth by C-section at 38 weeks. Find a hospital where you have access to both neonatal intensive care and pediatric surgeons. (Your doctor can help you choose one.)

If your child has signs of a cystic hygroma after he or she is born, your baby may get tests including chest X-ray, ultrasound, and an MRI or CT scan to diagnose the cyst.


Doctors use surgery to remove a cystic hygroma. If parts of it are left behind, there’s a 15% chance it will come back. Other options include chemotherapy, radiation therapy, steroids, and sclerotherapy (injection of a salt solution), though these are less effective than surgery.

As a parent, you may want to get support through groups focused on this condition, such as the nonprofit Birth Defect Research for Children and the Lymphatic Education and Research Network.

WebMD Medical Reference Reviewed by Dan Brennan, MD on February 19, 2019



National Institutes of Health: “Cystic Hygroma.”

Johns Hopkins Medicine: “Cystic Hygroma.”

The Fetal Medicine Foundation: “Cystic Hygroma.”

Kaiser Permanente: “Prenatal Ultrasound Findings: What Is a Cystic Hygroma?”

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