<unk>  (Latin for 'split<unk> ';<unk>  is a birth defect in which there is incomplete closing of the<unk>  and the membranes around the<unk> l cord during early development in pregnancy. There are three main types:<unk>  occulta, meningocele and myelomeningocele. Meningocele and myelomeningocele may be grouped as<unk>  cystica. The most common location is the lower back, but in rare cases it may be in the middle back or neck. Occulta has no or only mild signs, which may include a hairy patch, dimple, dark spot or swelling on the back at the site of the gap in the<unk> . Meningocele typically causes mild problems, with a sac of fluid present at the gap in the<unk> . Myelomeningocele, also known as open<unk> , is the most severe form. Problems associated with this form include poor ability to walk, impaired bladder or bowel control, accumulation of fluid in the brain (hydrocephalus), a tethered<unk> l cord and latex allergy. Learning problems are relatively uncommon.<unk>  is believed to be due to a combination of genetic and environmental factors. After having one child with the condition, or if one of the parents has the condition, there is a 4% chance that the next child will also be affected. Not having enough folate (vitamin B9) in the diet before and during pregnancy also plays a significant role. Other risk factors include certain antiseizure medications, obesity and poorly controlled diabetes. Diagnosis may occur either before or after a child is born. Before birth, if a blood test or amniocentesis finds a high level of alpha-fetoprotein (AFP), there is a higher risk of<unk> . Ultrasound examination may also detect the problem. Medical imaging can confirm the diagnosis after birth.<unk>  is a type of neural tube defect related to but distinct from other types such as anencephaly and encephalocele. Most cases of<unk>  can be prevented if the mother gets enough folate before and during pregnancy. Adding folic acid to flour has been found to be effective for most women. Open<unk>  can be surgically closed before or after birth. A shunt may be needed in those with hydrocephalus, and a tethered<unk> l cord may be surgically repaired. Devices to help with movement such as crutches or wheelchairs may be useful. Urinary catheterization may also be needed. Rates of other types of<unk>  vary significantly by country, from 0.1 to 5 per 1,000 births. On average, in developed countries, including the United States, it occurs in about 0.4 per 1,000 births. In India, it affects about 1.9 per 1,000 births. Europeans are at higher risk compared to Africans.
Spina bifida
Teratoma
Hydranencephaly
Anencephaly
Lissencephaly
Exencephaly
Schizencephaly
Cranioschisis