May also be called: Meningomyelocele; Spina Bifida; Open Spinal Dysraphism Myelomeningocele (my-uh-low-meh-NIN-guh-seel) is a type of spina bifida. Spina bifida is a birth defect that happens when the spinal cord and the membranes that cover and protect the brain and spinal cord (meninges) push through an abnormal hole in the back and form a fluid-filled sac. More to Know Spina bifida, which happens at the end of the first month of pregnancy, is a birth defect that occurs when the spinal cord or its coverings don't develop completely. In spina bifida, the two sides of an embryo's spine fail to join together, leaving an open area in the back. In some cases, the spinal cord or other membranes push through this opening. If just the meninges push through, the condition is called meningocele. Myelomeningocele happens when both the meninges and the spinal cord push through. Myelomeningocele is the most severe form of spina bifida. Because of the abnormal development of and damage to the spinal cord, a child with myelomeningocele usually has some paralysis. The degree of paralysis depends on where the opening is in the spine. The higher the opening is on the back, the more severe the paralysis tends to be. Most babies born with myelomeningocele also have hydrocephalus, a buildup of fluid in and around the brain. Myelomeningocele is usually detected in prenatal screening tests before a baby is born and treated with surgery after birth. During the surgery, doctors push the spine back into the vertebrae (the small, ring-like bones that make up the spinal column) and close the hole to prevent infection and protect the spine. Keep in Mind With the right treatment and ongoing care, most kids born with myelomeningocele can expect to lead a productive life and have a relatively normal life span. However, some amount of paralysis or weakness in the legs usually can be expected due to nerve damage. As a result, many kids with myelomeningocele will use wheelchairs to get around. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles Birth Defects Some birth defects are minor and cause no problems; others cause major disabilities. Learn about the different types of birth defects, and how to help prevent them. Read More Spina Bifida Spina bifida is a birth defect that involves the incomplete development of the spinal cord or its coverings. It's usually detected before a baby is born and treated right away. Read More Folic Acid and Pregnancy One of the most important things you can do to help prevent serious birth defects in your baby is to get enough folic acid every day - especially before conception and during early pregnancy. Read More Prenatal Genetic Counseling Genetic counselors work with people who are either planning to have a baby or are pregnant to determine whether they carry the genes for certain inherited disorders. Find out more. Read More Going to an Occupational Therapist Occupational therapy helps children overcome obstacles to be as independent as possible. Learn more about OT. Read More When Your Baby Has a Birth Defect If your child has a birth defect, you don't have to go it alone - many people and resources are available to help you. Read More Hydrocephalus Often called "water on the brain," hydrocephalus can cause babies' and young children's heads to swell to make room for excess cerebrospinal fluid. Learn how this condition is managed. Read More Prenatal Tests: FAQs Every parent-to-be hopes for a healthy baby, but it can be hard not to worry. Find out what tests can keep you informed of your health — and your baby's — throughout pregnancy. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.