What is Spina Bifida?
Spina Bifida is the most common permanently disabling birth defect that is compatible with life — and every person it affects is unique.
Spina Bifida affects approximately 166,000 Americans. It is a neural tube defect that happens within the first 28 days of pregnancy, when the neural tube fails to develop or close properly. Because severity varies significantly depending on the size and location of the opening on the spine, Spina Bifida is often called the “snowflake condition” — no two people are affected the same way.
What causes Spina Bifida?
The precise cause remains unknown. Medical experts believe a complex mix of both genetic and environmental factors act together to cause the condition.
Neural tube defects like Spina Bifida are not entirely understood, and Spina Bifida is not something that is caused by the actions of the parents.
Prenatal detection
Three testing methods are commonly used to detect Spina Bifida before birth:
- Alpha-fetoprotein (AFP) screening (weeks 16–18): elevated in approximately 75–80% of affected pregnancies.
- Ultrasound / sonogram: visualizes spinal abnormalities.
- Amniocentesis: analyzes protein levels in the amniotic fluid.
No medical test is perfect and the results are not always 100 percent accurate.
The three primary types
Spina Bifida Occulta (SBO)
Often called “hidden Spina Bifida.” About 15% of healthy people have it and never know. It is usually harmless and found by accident during unrelated imaging; some cases involve a tethered cord requiring neurosurgical review.
Meningocele
Part of the spinal cord comes through the spine like a sac. The sac holds nerve fluid, usually with no nerve damage, resulting in minor disability.
Myelomeningocele
The most severe form (Spina Bifida Cystica), where parts of the spinal cord and nerves come through the open spine. Seventy to ninety percent of affected children develop hydrocephalus.
Additional variations include Occult Spinal Dysraphism (OSD), Lipomyelomeningocele, Fatty Filum Terminale, Split Cord Malformation and Terminal Myelocystocele.
Treatment approaches
- Myelomeningocele: surgery within two to three days of birth helps prevent infection and minimizes further spinal cord damage.
- Meningocele: surgical treatment typically results in normal function without paralysis.
- OSD: early surgical consultation is recommended to prevent progressive neurological damage.
- Spina Bifida Occulta: generally requires no treatment.
Prevention with folic acid
All women of childbearing age should take a vitamin with 400 mcg (0.4 mg) of folic acid each day throughout their reproductive years — because many pregnancies are unplanned.
Women at higher risk (a personal or family history of Spina Bifida) should take 4,000 mcg (4.0 mg) of folic acid for one to three months before and during the first three months of pregnancy. The recurrence risk is approximately three percent. Always consult your health care provider.
Questions about a diagnosis?
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