Ovarian Cysts


A fetal ovarian cyst is a fluid-filled sac that forms on or inside the ovary of a female fetus.

Fetal ovarian cysts are a type of birth defect known as “intra-abdominal” cysts – growths or masses located inside the fetal abdomen.

The ovarian cyst may be on one side only (unilateral) or on both ovaries (bilateral). Ovarian cysts are classified as simple (a thin wall with a single cavity) or complex (thick-walled, with multiple partitions or “septations”). In most cases the cyst is simple and unilateral.

It is extremely rare for a fetal ovarian cyst to be malignant.

Cause and Prevalence

Ovarian cysts are believed to develop when the female fetus is exposed to hormones from the mother and the placenta that stimulate the ovary. They are known as congenital defects, meaning they are present at birth.

Ovarian cysts are the most common type of abdominal cyst diagnosed in female fetuses, occurring in an estimated 1 out of every 2,500 live births.

How does an ovarian cyst affect my baby?

If the ovarian cyst is large (greater than 5 cm), potential complications include:

  • Pressure on the fetal intestines, causing a blockage in the digestive tract
  • Polyhydramnios (build-up of amniotic fluid in the womb) if the intestines are blocked, preventing the fetus from swallowing the amniotic fluid as normal
  • Ovarian torsion (twisting of the ovary), cutting off blood flow and oxygen supply to the ovary and causing tissue death (necrosis)
  • Fetal ascites (fluid build-up in the fetal abdomen) caused by rupture of the ovarian cyst
  • Intra-cystic hemorrhage (bleeding within the cyst)
  • Need for surgery after birth to remove the ovary


Fetal ovarian cysts may be diagnosed during a routine prenatal ultrasound, typically in the third trimester.

Magnetic resonance imaging (MRI) may also be used to help distinguish ovarian cysts from other types of fetal abdominal masses, ensuring proper treatment planning.

In some cases the imaging may detect a “daughter cyst,” a cyst within the cyst, which is characteristic of ovarian cysts.

If torsion or hemorrhage has occurred, the ovarian cyst may appear as a solid mass on imaging.

Specialized Evaluation and Prenatal Care

If an ovarian cyst is diagnosed or suspected during pregnancy, you may be referred to a fetal center for further evaluation.

At Texas Children’s Fetal Center, we arrange for you to visit as quickly as possible for a comprehensive assessment by a team of specialists experienced in the diagnosis and treatment of fetal abdominal cysts, including maternal-fetal medicine physicians (OB/GYNs specializing in high-risk pregnancies), fetal imaging experts, pediatric surgeons, genetic counselors and neonatologists.

Additional testing will be performed using state-of-the-art imaging technologies and techniques that provide detailed views of your baby’s condition, for the most accurate diagnosis and treatment planning.

Our specialists will then meet with you about the results, discuss treatment recommendations and answer any questions you have. A diagnosis during pregnancy enables your family and your healthcare team to plan ahead for the specialized expertise your baby will need after birth, for timely treatment.

Pregnancy and Delivery

You and your baby will be closely monitored throughout pregnancy with more frequent ultrasounds to detect any changes in the cyst or signs of complications.

In rare cases, fetal intervention may be recommended if the cyst is large and poses risks to the fetus or pregnancy. Fetal intervention involves an in utero, ultrasound-guided procedure that uses a needle to drain the fluid from the cyst (aspiration), reducing its size. Your healthcare team will thoroughly explain the risks and benefits of fetal intervention to help you make an informed decision that’s right for your family.

If surgical intervention will be necessary shortly after birth, we recommend delivery at a center with pediatric surgeons experienced in the treatment of fetal ovarian cysts and the highest level of neonatal intensive care (NICU).

Treatment After Birth

After birth, an ultrasound will be performed to evaluate your baby’s ovarian cyst and determine treatment.

Treatment strategies include:

  • Observation only. In most cases a fetal ovarian cyst will resolve on its own within the first few months after birth. The baby will be monitored with regular ultrasounds to confirm the cyst goes away.
  • Surgery to remove or drain the cyst. Surgery to remove a cyst is called cystectomy. It is usually performed through a minimally invasive approach known as laparoscopy. Surgery may be recommended if:
    • The cyst doesn’t resolve on its own after a reasonable period
    • The cyst grows larger
    • The cyst is causing the baby symptoms
    • The cyst is large and blocking the intestines or putting the baby at risk of ovarian torsion
  • Surgery to remove the ovary. In rare cases, the ovarian cyst may damage the baby’s ovary or require removal of the ovary (known as an oophorectomy). Girls with one functioning ovary will still go through puberty and be able to achieve pregnancy. 

Postnatal Care Team

Depending on your baby’s symptoms, her postnatal care team may include:

A unique and distinct advantage for mothers delivering at Texas Children’s Pavilion for Women is our location inside Texas Children’s Hospital, consistently ranked one of the best children’s hospitals in the nation by U.S. News & World Report, for seamless access to the critical care services and specialists your child may need.

Our Fetal Center team works closely with Texas Children’s Pediatric Surgery Division and Texas Children’s Pediatric and Adolescent Gynecology Division, carefully planning and coordinating your baby’s postnatal care. This means no transfers after delivery. It also means the pediatric specialists responsible for treating your newborn girl have been an integral part of her care team since before birth.

The Pediatric and Adolescent Gynecology Division at Texas Children’s Hospital is one of the few established programs for the surgical treatment of pediatric and adolescent gynecologic disorders in the United States and the largest such program in Texas.

Why Texas Children’s Fetal Center?

  • A single location for expert maternal, fetal and pediatric care. At Texas Children’s Hospital, mother and baby receive the specialized care required for the diagnosis and treatment of fetal ovarian cysts all in one location, for highly coordinated care and treatment planning, including immediate access to our level IV NICU, if needed.
  • A skilled, experienced team with proven outcomes. We have a dedicated team of maternal-fetal medicine specialists, fetal imaging experts, neonatologists, pediatric surgeons and anesthesiologists, and others who work in concert to care for you and your baby every step of the way, using proven protocols we’ve developed over the years. With their combined expertise and unified approach, this team offers the best possible care for pregnancies involving fetal intra-abdominal cysts
  • We care for your child’s needs at every stage of life. Our comprehensive approach starts with your first prenatal visit and continues through delivery, postnatal care, childhood and adolescence, as needed, thanks to one of the nation’s leading teams of fetal and pediatric specialists for the care and treatment of birth defects.

For more information or to schedule an appointment,

call Texas Children’s Fetal Center at 832-822-2229 or 1-877-FetalRx (338-2579) toll-free.

Our phones are answered 24/7. Immediate appointments are often available.