Anencephaly is a neural tube defect (a disorder involving incomplete development of the brain, spinal cord, and/or their protective coverings). The neural tube is a narrow sheath that folds and closes between the 3rd and 4th weeks of pregnancy to form the brain and spinal cord of the embryo. Anencephaly occurs when the "cephalic" or head end 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 both a forebrain (the front part of the brain) and a cerebrum (the thinking and coordinating area of the brain). The remaining brain tissue is often exposed--not covered by bone or skin. The infant is usually blind, deaf, unconscious, and unable to feel pain. Although some individuals with anencephaly may be born with a rudimentary brain stem, the lack of a functioning cerebrum permanently rules out the possibility of ever gaining consciousness. Reflex actions such as respiration (breathing) and responses to sound or touch may occur. The cause of anencephaly is unknown. Although it is believed that the mother's diet and vitamin intake may play a role, scientists believe that many other factors are also involved.
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Anencephaly Support Foundation
20311 Sienna Pines Court
Spring, TX 77379
Association of Birth Defects Children
930 Woodcock Road
Orlando, FL 32803
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
National Organization for Rare Disorders (NORD)
P.O. Box 8923 (100 Route 37)
New Fairfield, CT 06812-8923
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The National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892