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Agenesis of the Corpus Callosum

The corpus callosum is a band of nerve fibers that connects the two sides, or hemispheres, of the brain. These nerve fibers enable the left and right sides of the brain to communicate with each other.

In a small number of babies, the corpus callosum is either partially or completely missing. This birth defect is called agenesis of the corpus callosum (ACC).

Agenesis of the Corpus Callosum Treatment: Why Choose Us?

At the Fetal Care Center, we use the most advanced technology to diagnose ACC in unborn babies. Our ultrasound experts perform more than 5,000 obstetrical and gynecological ultrasound tests every year. We’re experts at detecting problems early.

If your unborn baby has ACC, our high-risk pregnancy doctors and pediatric specialists work together to provide personalized care throughout pregnancy, delivery and beyond.

About Agenesis of the Corpus Callosum

ACC is one of the most common congenital brain abnormalities. The condition affects approximately 2 to 7 out of every 1,000 newborns. Children with ACC often have other brain abnormalities.

Many babies with ACC develop normally. Nearly half of all babies with ACC have additional types of birth defects, some of which cannot be detected before birth. These children may experience:

  • Seizures
  • Vision and hearing problems
  • Developmental delays, including speech and learning difficulties
  • Physical development problems, including delays in sitting, crawling and walking
  • Signs of attention deficit disorder (ADD) or obsessive-compulsive behaviors 

Causes of Agenesis of the Corpus Callosum

While there is no definitive cause of ACC, certain factors increase risk, such as:

  • Chromosomal abnormality inherited from one or both parents
  • Infection or injury during the second trimester of pregnancy

Our genetic counselors can help you understand your future risk of having another child with ACC.

Diagnosing Agenesis of the Corpus Callosum

To diagnose ACC via ultrasound, our doctors look for:

  • Missing corpus callosum
  • Enlarged cerebral ventricles, fluid-filled regions in the center of the brain
  • Missing cavum septum pellucidum, a small, fluid-filled area in the center of the brain

ACC can be difficult to diagnose with certainty by ultrasound alone. Your doctor may recommend additional tests, such as:

  • Fetal magnetic resonance imaging (MRI): This noninvasive imaging procedure uses a magnetic field (not radiation) to provide detailed information about your unborn baby’s brain. The procedure is safe for your baby. Our radiologists have extensive experience performing and interpreting fetal MRIs.
  • Genetic amniocentesis: This test of amniotic fluid detects chromosomal abnormalities. Our maternal-fetal medicine specialists are among the most experienced amniocentesis experts in the St. Louis metropolitan area.

A maternal-fetal medicine specialist is always present during diagnostic procedures to quickly explain your unborn baby’s condition and treatment options.

Treating Agenesis of the Corpus Callosum

While there is no treatment that can restore a missing corpus callosum, certain interventions during childhood can help your child develop and grow. Physical, occupational and speech therapies can address developmental difficulties. Medication can decrease seizure frequency. The pediatric specialists at St. Louis Children’s Hospital work with you to develop the best care plan for your child’s specific needs.

During your pregnancy, you receive care from maternal-fetal medicine specialists at the Fetal Care Center. These obstetrician-gynecologists specialize in caring for women whose unborn babies are at risk for health complications. Throughout your pregnancy, you may have several ultrasounds to check on your baby’s growth and the size of your baby’s ventricles.

We recommend that you deliver at a hospital equipped to care for a high-risk pregnancy, such as the Women & Infants Center. In most cases, you should be able to have a vaginal delivery. After delivery, your baby may receive advanced medical care in our Level IV newborn intensive care unit (NICU). Our focus is on keeping mom and baby together, which is why our NICU is connected to labor and delivery. Your baby may have a brain ultrasound or MRI while in the hospital to check for additional birth defects or a genetic problem.

Contact Us

To make an appointment with a Washington University fetal care specialist at the Women & Infants Center, call 855.925.0631.