Open Neural Tube Defects (ONTD) and Myelomeningocele (MMC)

At the University of Chicago Medicine’s Fetal and Neonatal Care Center (FNCC), our experts work together to care for babies with myelomeningocele and other open neural tube defects.

We offer:

• Help and guidance before birth (prenatal counseling)
• Planning for a safe delivery
• Surgery shortly after birth to help repair the spine

Find a maternal-fetal medicine specialist

What are open neural tube defects?

Open neural tube defects are birth defects of the brain and spinal cord. They happen when the neural tube does not close properly early in pregnancy.

What is myelomeningocele?

Myelomeningocele, often called MMC, is a type of spina bifida. It is the most common kind of open neural tube defect. With MMC, a sac that holds part of the spinal cord and nerves pushes through the opening in the baby's spine. Because these nerves are on the outside of the baby's back, they can get damaged or infected.

This can cause:

• Weakness or trouble moving the legs
• Bladder or bowel problems
• Hydrocephalus (extra fluid in the brain)
• Bone or foot problems (like clubfoot or scoliosis)

How do we diagnose MMC?

• Most MMC cases are found during a second-trimester ultrasound.
• Doctors may see a spinal defect or a bulging sac.
• Sometimes the shape of the baby’s head or brain looks different.
• Fetal MRI helps us see more details.
• Amniocentesis may help find other genetic problems.

What to Expect Before, During and After Delivery

Before Birth

• You will have a full check-up, with ultrasound and MRI.
• You will talk with a genetic counselor and have an amniocentesis.
• You will meet our team: neurosurgeons, neonatologists, neurologists, orthopedic surgeons, developmental pediatricians and urologists.

Delivery Planning

• We work with you to make a safe delivery plan, which may include a planned cesarean delivery
• Your baby will receive expert care in our top-level NICU.

After Birth

• Our neonatology team protects your baby’s spinal sac to prevent infection.
• In the first day or two, our neurosurgical team performs surgery to close the opening.
• We monitor and treat hydrocephalus.
• Our pediatric urologists, orthopedic surgeons, and physical therapists are available as needed.

Risks and Long-Term Outcomes

MMC can cause lifelong challenges, such as:

• Paralysis
• Trouble moving or walking
• Bladder and bowel problems
• Hydrocephalus that may need ongoing care, including surgery
• Breathing problems during sleep
• Learning or developmental delays

Getting early help and having a team by your side can make a big difference.

Need help or have questions about MMC?

The first step is a consultation.

Call us at 773-702-6118 to learn more.