Neural tube defects include anencephaly, encephalocoele and spina bifida. Spina bifida is the most common form of neural tube defect resulting in continued life after birth. It occurs when the lower part of the neural tube, which develops into the spinal cordand the bones that enclose them, does not close properly, leaving the spinal cord exposed or covered only with skin. Babies born with spina bifida may have a wide range of physical disabilities, such as loss of bladder and bowel control, paralysis of the legs and associated hydrocephalus. Anencephaly is a fatal condition in which the upper end of the neural tube does not close and the brain fails to completely develop or is entirely absent.
Pregnancies affected by anencephaly often result in miscarriages, stillbirth or neonatal death.
Encephalocoele is when part of the brain or surrounding membranes protrude through a defect in the skull. It is very rare. Any woman of child bearing age has the potential to have a baby affected by a neural tube defect. Absence of a family history or previous birth of unaffected children are not protective factors. There is also no evidence to suggest that the risk of neural tube defects are linked with socio-economic status, specific ethnic groups or races.