Umbilical Cord Cyst

Umbilical cord cysts are fluid-filled sacs that can form in an umbilical cord. Healthcare providers usually find these cysts during a pregnancy ultrasound in the first trimester. Most of the time, these cysts don’t cause harm and go away on their own. But sometimes, they can be a sign of a complication. If your provider finds one, they may monitor it closely or recommend further testing.

There are two types of umbilical cord cysts:

• True cysts: This type forms out of leftover tissue during fetal development. These cysts are found near where the cord connects to the fetus. They usually don’t cause problems.
• Pseudocysts (false cysts): This type is more common. The cysts can develop anywhere along the umbilical cord. They’re made from a substance in the cord called Wharton's jelly. While many are harmless, they can be a sign of a pregnancy complication.

Umbilical cord cysts happen in about 1 in 100 pregnancies.

Symptoms of an umbilical cord cyst

There are no symptoms of an umbilical cord cyst. It’s something that your provider will find during a routine ultrasound.

Umbilical cord cyst causes

The cause usually depends on the type of cyst. But there may not be one clear cause.

Healthcare providers know that true cysts happen when leftover tissue from the embryo forms a fluid-filled sac. Typically, the tissue disappears as the embryo grows into a fetus. But with a true cyst, this doesn’t happen. Experts aren’t entirely sure why.

Pseudocysts happen when a substance called Wharton's jelly swells with fluid or breaks down in one spot. This jelly cushions the blood vessels in the umbilical cord. Experts aren’t entirely sure why this happens. But they do know it relates to abnormal fetal development.

Complications

Many cysts are harmless. But it can depend on their size, type and when they're found. Large or multiple cysts can press down on the cord. This can block blood flow to the fetus.

Other complications can include:

• Genetic or chromosomal conditions: Umbilical cord cysts can be related to Down syndrome, Trisomy 18 or Trisomy 13. This happens more often when the cyst is found later in pregnancy or there are other problems with the fetus.
• Growth problems: Sometimes, a cyst can cause intrauterine growth restriction (IUGR).
• Increased risk for a C-section: Your provider may suggest a C-section if the cyst is large or there are signs of fetal distress.

How doctors diagnose an umbilical cord cyst

Your pregnancy care provider will diagnose an umbilical cord cyst after an ultrasound. What they do next depends on the cyst's location, type and size, and how many weeks pregnant you are.

If it's a true cyst, your provider may monitor it closely to see if it changes over time. This typically involves having extra ultrasounds.

Healthcare providers will recommend more tests if you have a large pseudocyst. They’ll also recommend additional testing if they find it during your second or third trimesters. Specific tests may include:

• Advanced ultrasound: This detailed ultrasound takes a closer look at the fetal organs for signs of problems.
• Prenatal genetic testing: These blood tests tell you how likely it is that the fetus has a genetic disorder.
• Amniocentesis: This test uses a sample of amniotic fluid to diagnose certain congenital disorders.

What is the treatment for an umbilical cord cyst?

Most true umbilical cord cysts don’t need treatment. If there are no signs of other problems and the cyst is found in the first trimester, it's usually harmless. Your provider may recommend extra ultrasounds to monitor the cyst. Often, it goes away on its own.

Your provider will recommend further testing if any of the following are true:

• The cyst is large.
• It appears after 12 weeks of pregnancy.
• An ultrasound shows other concerns.

Further tests can confirm if the fetus has a genetic or chromosomal condition. Your provider may also refer you to a maternal-fetal medicine specialist.

Removing an umbilical cord cyst isn’t possible. Instead, your provider will plan the safest way to deliver your baby. Sometimes, this includes a preterm delivery or a C-section delivery.

The goal is to keep everyone safe by managing any risks or complications the cyst could cause.

What is the outlook for an umbilical cord cyst?

The outlook for umbilical cord cysts is good. This is especially true if the cyst is small, found early and not linked to any other abnormalities. These cysts often go away on their own and don’t affect the pregnancy or your baby.

A cyst may cause worry when it’s a pseudocyst, especially when it’s found later in pregnancy and accompanied by other unexpected ultrasound results. In these cases, your provider will monitor you closely for the rest of your pregnancy. They may also order tests that can tell you if your baby will be born with a health condition. If there are signs of problems during pregnancy, delivery may be the safest option.