A fetal abdominal
is a bubble of fluid in a balloon-like bag in an unborn baby's belly.
What Happens With a Fetal Abdominal Cyst?
A fetus can have one fetal abdominal cyst, or more. The most common types include:
enteric (en-TARE-ik) duplication cysts: these
form when the digestive
tract splits as it's forming
mesenteric (mez-en-TARE-ik) cysts: these form
in the mesentery. The mesentery (MEZ-en-tare-ee) attaches to the intestines and contains
the blood vessels that supply them.
genitourinary (jen-ih-toe-YUR-ih-nair-ee) cysts:
these form on a kidney,
(urine-carrying tube), or the bladder
choledochal (KOLE-uh-dok-ul) cysts: these form
from the bile ducts in or near the liver
In a female fetus, the most common type of a fetal abdominal cyst is an ovarian
A cyst can cause problems if it:
blocks the digestive tract
makes an organ twist until its blood vessels are squeezed shut. This is called
torsion (TOR-shun). An organ with blocked blood vessels doesn't get
enough oxygen, so part or all of it can die.
Fetal abdominal cysts usually don't cause problems unless they get very large.
A big cyst can put pressure on the baby's developing lungs and other organs. This
can cause problems such as:
too much fluid in the womb (uterus)
fluid build-up in the belly
blockage of the intestines
What Are the Signs & Symptoms of a Fetal Abdominal Cyst?
The cysts usually don't cause any symptoms during the pregnancy.
Sometimes doctors can feel the cyst in the baby's belly after birth. Other symptoms
of a fetal abdominal cyst after birth include:
crying and fussiness due to pain
yellow-tinted skin and eyes (jaundice)
Cysts that are more than 2 inches (5 cm) across may also cause:
a difficult delivery because of the cyst's size
trouble breathing if the cyst presses on the
so the baby's lungs
can't expand well
What Causes a Fetal Abdominal Cyst?
Most fetal abdominal cysts happen when an accidental slip in the normal growth
process makes an extra layer or bubble that fills with fluid. Doctors don't know why
it happens. There is nothing the baby's parents can do to keep a fetal abdominal cyst
Ovarian cysts often happen because the unborn baby is exposed to the mother's hormones. There is nothing
the baby's mother can do to prevent one.
A fetal abdominal cyst is not a cancer.
How Is a Fetal Abdominal Cyst Diagnosed?
A routine ultrasound
scan of an unborn baby usually will find a fetal abdominal cyst. An imaging specialist
(a radiologist) will study the cyst's:
By studying the images of the cyst and how it changes with gentle pressure, the
radiologist might be able to tell what kind it is. Knowing the type of cyst helps
the baby's doctors know what kind of special care, if any, is needed at birth or in
the first few weeks of life.
If the screening prenatal ultrasound doesn't show what kind of cyst the baby has,
the radiologist may:
Doctors make a plan for treating a fetal abdominal cyst based on:
the type of cyst
how the cyst changes and grows during the pregnancy
The obstetrician (pregnancy specialist) and radiologist will check the cyst with ultrasound scans every few weeks
until birth. The doctors work as a team to decide if a C-section
delivery is best. But most babies with fetal abdominal cysts are delivered through
Surgery to remove a cyst (cystectomy) is sometimes needed to keep
it from blocking the digestive tract or to prevent torsion. Pediatric surgeons usually
use minimally invasive
surgery (laparoscopy) to remove cysts.
After birth, a baby isn't exposed to the mother's hormones. So an ovarian cyst
usually goes away on its own within a few months. The baby's doctor checks ultrasound
scans regularly to be sure the cyst goes away.
A large fetal ovarian cyst — one that is more than about 2 inches (5 cm) across
— can twist on its stem and squeeze off the blood vessels that carry blood to and
from the ovary. To prevent this, doctors usually:
do an ultrasound scan soon after birth
recommend surgery to drain or remove the cyst
For a smaller fetal ovarian cyst, the baby's doctor will order an ultrasound scan
during the first few weeks after birth to:
confirm the type of cyst
If the cyst doesn't go away on its own, the doctor may recommend a cystectomy to
What Else Should I Know?
Sometimes, treating an ovarian cyst requires removal of the ovary it grew from.
The ovary on the other side can release enough hormones and eggs for normal sexual
development and pregnancy later in life.