It is a defect in the closure of the neural tube during fetal development. The neural tube is a narrow channel that folds and closes between the 3rd and 4th weeks of pregnancy to form the brain and spinal cord of the embryo. The “cephalic” or head of the neural tube fails to close, resulting in the absence of a major portion of the brain, skull, and scalp.
Infants with this disorder are born without a forebrain (front part of brain) and a cerebrum (thinking and coordinating part of the brain). The remaining brain tissue is often exposed.
A baby born with anencephaly is usually blind, deaf, unconscious, and unable to feel pain. Some can be born with a rudimentary brain with if the lack of a functioning cerebrum permanently rules out the possibility of ever gaining consciousness but reflex actions such as breathing may occur. If the infant if not stillborn, then he or she will usually die within a few hours or days after birth.
The cause is unknown. Although it is thought that a mother’s diet and vitamin intake may play a role, scientists believe that many other factors are also involved. Recent studies show that addition of folic acid to the diet of women of childbearing age may significantly reduce the incidence of neural tube defects. (0.4 mg daily)
Folate and folic acid are forms of a water-soluble B vitamin. Folate occurs naturally in food. Folate is necessary for the production and maintenance of new cells. This is especially important during periods of rapid cell division and growth such as infancy and pregnancy. Folate is needed to make DNA and RNA, the building blocks of cells. It also helps prevent changes to DNA that may lead to cancer. what foods provide folate? Leafy greens such as spinach and turnip greens, dry beans and peas, fortified cereals and grain products, and some fruits and vegetables are rich food sources of folate. Some breakfast cereals (ready-to-eat and others) are fortified with 25 percent or 100 percent of the Daily Value (DV) for folic acid.
- Some situations that increase the need for folate include:
- pregnancy and lactation (breastfeeding)
- alcohol abuse
- kidney dialysis
- liver disease
- certain anemias.
Suggestive screening test
- It is common to screen a woman’s blood for alpha fetoprotein.
- A high level of AFP suggests a fetus with a neural tube defect.
- Amniocentesis can also help detect neural tube defects by measuring AFP.
- There is no cure or standard treatment for this birth defect.
Are you related?
- Couples that have had a previous child with a neural tube have a 1 in 40 chance of recurrence.
- More distant (second degree) relatives to an individual such as nieces or nephews would have a 1 in 200 risk of a neural tube defect.
- Third degree relatives such as cousins have a 1 in 400 risk for a neural tube defect.
- And fourth degree would have a risk similar to general population 1 in 670