Risk factors

Spina bifida is more common among whites and Hispanics, and females are affected more often than males. Although doctors and researchers don't know for sure why spina bifida occurs, they have identified some risk factors:

• Folate deficiency. Folate, the natural form of vitamin B-9, is important to the development of a healthy baby. The synthetic form, found in supplements and fortified foods, is called folic acid. A folate deficiency increases the risk of spina bifida and other neural tube defects.
• Family history of neural tube defects. Couples who've had one child with a neural tube defect have a slightly higher chance of having another baby with the same defect. That risk increases if two previous children have been affected by the condition. In addition, a woman who was born with a neural tube defect has a greater chance of giving birth to a child with spina bifida. However, most babies with spina bifida are born to parents with no known family history of the condition.
• Some medications. For example, anti-seizure medications, such as valproic acid (Depakene), seem to cause neural tube defects when taken during pregnancy. This might happen because they interfere with the body's ability to use folate and folic acid.
• Diabetes. Women with diabetes who don't have well-controlled blood sugar have a higher risk of having a baby with spina bifida.
• Obesity. Pre-pregnancy obesity is associated with an increased risk of neural tube birth defects, including spina bifida.
• Increased body temperature. Some evidence suggests that increased body temperature (hyperthermia) in the early weeks of pregnancy may increase the risk of spina bifida. Elevating your core body temperature, due to fever or using a sauna or hot tub, has been associated with a possible slightly increased risk of spina bifida.

If you have known risk factors for spina bifida, talk with your doctor to determine if you need a larger dose or prescription dose of folic acid, even before a pregnancy begins.

If you take medications, tell your doctor. If you plan ahead, some medications can be adjusted to diminish the potential risk of spina bifida.