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Genetic and Rare Diseases Information Center (GARD)

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Spina bifida

Other Names for this Disease
  • Cleft spine
  • Open spine
  • Rachischisis
  • Spinal dysraphism
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What is spina bifida?

What causes spina bifida?

What is spina bifida?

Spina bifida is a type of neural tube defect in which the bones of the spinal column do not close completely around the developing nerves of the spinal cord during the development of the embryo. As a result, part of the spinal cord may stick out through an opening in the spine, leading to permanent nerve damage. Children born with spina bifida often have a fluid-filled sac on their back covered by skin. If the sac contains part of the spinal cord and its protective covering, it is known as a myelomeningocele; if it does not, it is known as a meningocele. The signs and symptoms range from mild to severe (depending on the location and extent of spinal cord involvement) and can include a loss of feeling below the level of the opening; weakness or paralysis of the feet or legs; problems with bladder and bowel control; hydrocephalus; and learning problems. With surgery and other forms of treatment, many people with spina bifida live into adulthood. There is also a milder form of the condition called spina bifida occulta.[1]
Last updated: 5/9/2011

What causes spina bifida?

Spina bifida is a complex condition that is likely caused by the interaction of multiple genetic and environmental factors. Some of these factors have been identified, but many remain unknown. Changes in dozens of genes may influence the risk of spina bifida. The best-studied of these genes is MTHFR, which provides instructions for making the B-vitamin folate (also called folic acid or vitamin B9). Changes in other genes related to folate processing and genes involved in the development of the neural tube have also been studied as potential risk factors for spina bifida. However, none of these genes appears to play a major role in causing the condition.[1]

Researchers have also examined environmental factors that could contribute to the risk of spina bifida. A shortage (deficiency) of folate appears to play a significant role. Studies have shown that women who take supplements containing this vitamin before they get pregnant and very early in their pregnancy are significantly less likely to have a baby with spina bifida or a related neural tube defect. Other possible risk factors for spina bifida include diabetes mellitus, obesity, exposure to high heat (such as a fever or use of a hot tub or sauna) in early pregnancy, and the use of certain anti-seizure medications during pregnancy. However, it is unclear how these factors may influence the risk of spina bifida.[1]
Last updated: 5/9/2011

  1. Spina bifida. Genetics Home Reference. February 2011; Accessed 5/9/2011.