What is spina bifida?

Spina bifida, a type of neural tube defect (NTD), means "cleft spine," or an incomplete closure in the spinal column. This birth defect occurs between the fourth and sixth weeks of pregnancy when the embryo is less than an inch long.

Normally, a groove in the middle of the embryo deepens, allowing the sides to meet and enclose the tissue destined to be the spinal cord. In spina bifida, the sides of the embryo do not fully meet, resulting in a malformed neural tube that affects the spinal column and, in many cases, forms a spinal cord cleft, or lesion.

The most serious form of spina bifida may include muscle weakness or paralysis below the cleft area, loss of sensation, and loss of bowel and bladder control.

One out of 1,000 newborns in the United States is born with spina bifida; each year 4,000 pregnancies are affected by spina bifida.

About 95 percent of babies with spina bifida are born to parents with no family history. While spina bifida appears to run in certain families, it does not follow any particular pattern of inheritance.

Types of spina bifida

There are three general types of spina bifida (listed below from mild to severe):

Spina bifida occulta
This is an opening in one or more of the vertebrae (bones) of the spinal column without apparent damage to the spinal cord. It is estimated that 40 percent of all Americans may have spina bifida occulta, but because they experience few or no symptoms, very few of them ever know that they have it.

Meningocele
The meninges, or the protective covering around the spinal cord, pushes out through the opening in the vertebrae in a sac called the meningocele. The spinal cord remains intact; this can be repaired with little or no damage to the nerve pathways.

Myelomeningocele
This is the most severe form of spina bifida, in which a portion of the spinal cord itself protrudes through the back. In some cases, sacs are covered with skin; in others, tissue and nerves are exposed.

A large percentage of children born with myelomeningocele have a hydrocephalus, an accumulation of fluid in the brain that is controlled by a surgical procedure called shunting. This relieves the fluid build-up in the brain and reduces the risk of brain damage, seizures, or blindness.

In some cases, children with spina bifida who also have a history of hydrocephalus experience learning problems. They may have difficulty paying attention, expressing or understanding language, and grasping reading and math. Early intervention with children who experience learning problems can help considerably to prepare them for school and life.

Examples of secondary conditions associated with spina bifida are orthopedic problems, latex allergy, tendinitis, obesity, skin breakdown, gastrointestinal disorders, learning disabilities, depression, and social and sexual issues.

Although spina bifida is relatively common, until recently most children born with a myelomeningocele died shortly after birth. Now that surgery to drain spinal fluid and protect against hydrocephalus can be performed in the first 24-hours of life, children with myelomeningocele are much more likely to survive.

Quite often, however, they have a series of operations throughout childhood. Advances in surgery and urology make it possible for 90 percent of infants born with spina bifida to live full and active lives into adulthood.

It is estimated that about 70,000 people are living with spina bifida in the United States today.

Prevention

Birth defects can happen in any family. Women with certain chronic health problems, including diabetes and seizure disorders (treated with anticonvulsant medications), have an increased risk (approximately 1 out of 100) of having a baby with spina bifida.

Many things can affect a pregnancy, including family genes and things women may be exposed to during pregnancy. Recent studies have shown that folic acid is one factor that may reduce the risk of having an NTD baby.

Taking folic acid before and during early pregnancy reduces the risk of spina bifida and other neural tube defects. Folic acid, a common water-soluble B vitamin, is essential for the functioning of the human body. During periods of rapid growth, such as fetal development, the body's requirement for this vitamin increases.

The average American diet does not supply the recommended level of folic acid. It can be found in multivitamins, fortified breakfast cereals, dark green leafy vegetables such as broccoli and spinach, egg yolks, and some fruits and fruit juices.

According to the Spina Bifida Association of America (SBAA), if all women who could become pregnant were to take a multivitamin with 400 micrograms of folic acid, the risk of neural tube defects could be reduced by up to 75 percent.

There are three prenatal tests that usually detect spina bifida: a blood test for alpha-fetoprotein; ultrasound; and amniocentesis.

Children with spina bifida can achieve independence as they learn mobility skills with the use of crutches, braces, or wheelchairs. Many children can independently manage their bowel and bladder problems.

According to SBAA, it is important that attention be focused on the psychological and social development of children and young adults with spina bifida. Many recent studies, including SBAA's Adult Network Survey, clearly indicate the presence of emotional problems that result from factors such as low self-esteem and lack of social skills training.

Research and treatment

Researchers are looking for the genes linked to a predisposition to spina bifida. They are also exploring the complex mechanisms of normal brain development to see what goes wrong with the neural tube in spina bifida.

Since the 1930s, treatment of babies with this condition has been to surgically close the opening in their back within a few days of birth. This prevents further damage to the nervous tissue; however, it does not restore function to the already damaged nerves.

In recent years, some doctors have begun operating on babies with spina bifida before they are born. Nerve function in babies with spina bifida seems to worsen through the course of pregnancy. This progressive pattern of damage to the spinal cord may be caused by contact with amniotic fluid and suggests intervention as early as possible.

Many children with spina bifida have symptoms related to a tethered cord (the cord and the membranes that line it stick together, restricting spinal cord growth and spinal fluid movement). Better surgical techniques are now available to treat this, thus reducing pain and weakness and improving bowel and bladder function.

Spina bifida support and resources

If you are looking for more information on spina bifida or have a specific question, our information specialists are available business weekdays, Monday through Friday, toll-free at 800-539-7309 from 9am to 5pm ET.

Additionally, the Reeve Foundation maintains a spina bifida fact sheet with additional resources from trusted Reeve Foundation sources. Check out our repository of fact sheets on hundreds of topics ranging from state resources to secondary complications of paralysis.

We encourage you to reach out to spina bifida support groups and organizations, including:

  • Spina Bifida Association (SBA) promotes the prevention of spina bifida and works to enhance the lives of all affected. 202-944-3295 or toll-free 1-800-621-3141.
  • March of Dimes Birth Defects Foundation offers information about the four major problems that threaten the health of America's babies: birth defects, infant mortality, low birth weight, and lack of prenatal care. Toll-free 1-888-MODIMES (663-4637).

Sources: Spina Bifida Association, The National Institute of Neurological Disorders and Stroke, March of Dimes Birth Defects Foundation

This project was supported, in part by grant number 90PR3002, from the U.S. Administration for Community Living, Department of Health and Human Services, Washington, D.C. 20201. Grantees undertaking projects under government sponsorship are encouraged to express freely their findings and conclusions. Points of view or opinions do not, therefore, necessarily represent official Administration for Community Living policy.