The skin at the site of the lesion may be normal, or it may have some hair growing from it; there may be a dimple in the skin, or a birthmark. Unlike most other types of neural tube defects, spina bifida occulta is not associated with increased AFP, a common screening tool used to detect neural tube defects in utero. This is because, unlike in most of the other neural tube defects, the dural lining is maintained.Many people with this type of spina bifida do not even know they have it, as the condition is asymptomatic in most cases. A systematic review of radiographic research studies found no relationship between spina bifida occulta and back pain. More recent studies not included in the review support the negative findings.However other studies suggest spina bifida occulta is not always harmless. One study found that among patients with back pain severity is worse if spina bifida occulta is present.Incomplete posterior fusion is not a true spina bifida and is very rarely of neurological significance. Meningocele
A posterior meningocele () or meningeal cyst () is the least common form of spina bifida. In this form, a single developmental defect allows the meninges to herniate between the vertebrae. As the nervous system remains undamaged, individuals with meningocele are unlikely to have long-term health problems, although cases of tethered cord have been reported.
The U.S. Food and Drug Administration, Public Health Agency of Canada and the UK Department of Health and Social Care (DHSC) recommended amount of folic acid for women of childbearing age and women planning to become pregnant is at least 0.4 mg/day of folic acid from at least three months before conception, and continued for the first 12 weeks of pregnancy. Women who have already had a baby with spina bifida or other type of neural tube defect, or are taking anticonvulsant medication, should take a higher dose of 4–5 mg/day.Certain mutations in the gene VANGL1 have been linked with spina bifida in some families with a history of the condition. Screening
Open spina bifida can usually be detected during pregnancy by fetal ultrasound. Increased levels of maternal serum alpha-fetoprotein (MSAFP) should be followed up by two tests – an ultrasound of the fetal spine and amniocentesis of the mothers amniotic fluid (to test for alpha-fetoprotein and acetylcholinesterase). AFP tests are now mandated by some state laws (including California) and failure to provide them can have legal ramifications. In one case, a man born with spina bifida was awarded a $2-million settlement after court found his mothers OBGYN negligent for not performing these tests. Spina bifida may be associated with other malformations as in dysmorphic syndromes, often resulting in spontaneous miscarriage.