The exact causes of spina bifida are not known, though studies have uncovered several possible risk factors. Researchers have speculated that the condition, which impedes the full closure of the neural tube, has some connection to a variety of factors including environment, nutrition, drugs, and genetics. Conditions such as diabetes and obesity may also be risk factors. Research has shown that insufficient consumption of folic acid by the mother plays a role in the development spina bifida.
Family history is suspected to be one of the major causes of spina bifida. Pregnant woman with a connection to the defect, either by having it themselves, previously giving birth to an affected child, or who have close family members who were afflicted are at greater risk of having a child with spina bifida. Race is another possible factor, as incidences of spina bifida are higher among Hispanics and whites.
Researchers also suspect that improper nutrition is one of the causes of spina bifida. Studies have shown that the B vitamin folic acid plays a key role in fetal development and that when deficient, can contribute to spina bifida. Women who have previously had a close connection to the defect are usually required to supplement with extra folic acid.
Pregnant women are typically advised to start taking a prenatal vitamin with folic acid as soon as possible. The nutrient can also be found in egg yolks, dark leafy greens, and fortified foods. Some anti-seizure medications are thought to be a risk factor for spina bifida because they inhibit the absorption of folic acid in the body.
Other pre-existing conditions are also believed to be possible causes of spina bifida. Diabetes can be problematic if a pregnant woman is not able to balance her blood sugar properly. Spina bifida is one of the many possible birth defects that could affect children of obese women.
There is also evidence that increased body temperature during pregnancy could lead to spinal bifida. Women with a body temperature 3 to 4 degrees Fahrenheit (2 degrees Celsius) higher than normal are thought to be at an elevated risk for the disease. This increase can come from external heat such as from a sauna or hot tub, or as a result of fever.
Researchers continue to search for a specific cause for spina bifida. Genetics are the focus of most studies, including a search for the particular genes that cause the defect. Scientists also hope to determine whether fetal, rather than post-delivery surgery is a more effective way fix spina bifida.