Neural Tube Defects
(spina bifida and anencephaly)
Neural tube defects occur in 1 or 2 out of every 1000 pregnancies. They are birth defects in which the brain (anencephaly) or spine (spina bifida) does not form normally and may not be covered with bone or skin. Some babies with neural tube defects are stillborn or die shortly after birth. Children who survive usually have medical problems. Complications may include infections, hydrocephalus ("water on the brain"), and sometimes learning problems or mental retardation. Spina bifida often results in paralysis of the legs and impaired bowel and bladder control. Elevated levels of AFP indicate an increased risk for a fetus with a neural tube defect.