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Birth Defects Descriptions

Anencephaly

Anencephaly is a birth defect that affects the closing of the neural tube during pregnancy. The neural tube is a narrow channel that folds and closes during the third and fourth weeks of pregnancy to form the brain and spinal cord. Anencephaly occurs when the part of the neural tube that forms the brain does not close. This results in the baby lacking parts of the brain, skull, and scalp.

Cleft Lip

A cleft lip is a congenital defect of the upper lip in which there is incomplete closure. The opening in the lip can be a small slit in the lip or a large opening that goes through the lip into the nose.

Cleft Palate

A cleft palate is an opening in the roof of the mouth, called the palate. A cleft palate can occur when the two sides of the palate do not come together correctly.

Gastroschisis

A birth defect in which a portion of an infant’s intestines stick out of the body through a small hole in the body wall beside the umbilical cord. The body wall defect can be small or large and other organs such as the liver can be involved.

Hypoplastic Left Heart Syndrome

A type of congenital heart defect that affects normal blood flow through the heart. Several parts of the left side of the heart do not fully develop.

Hypospadias

A birth defect among boys in which the opening of the urethra is located somewhere along the underside of the penis instead of at the tip. The urethra is the tube that carries urine from the bladder to the outside of the body. This defect occurs when the urethra does not complete its development during the pregnancy.

Limb Deficiency

Upper limb deficiency defects occur when a part of or the entire arm (upper limb) of a fetus fails to form completely during pregnancy. Lower limb deficiency defects occur when a part of or the entire leg (lower limb) of a fetus fails to form completely during pregnancy.

Spina Bifida (without Anencephaly)

The neural tube is a narrow channel that folds and closes during the third and fourth weeks of pregnancy to form the brain and spinal cord. Spina bifida is a neural tube defect that happens if part of the neural tube does not close all the way.

Tetralogy of Fallot

A type of congenital heart defect that changes the normal flow of blood through the heart. Tetralogy of Fallot is a combination of four defects: (1) a hole in the wall between the ventricles (two lower chambers of the heart), called a ventricular septal defect; (2) narrowing of the tube that carries blood from the heart to the lungs, called pulmonary stenosis; (3) the aorta (the tube that carries oxygen-rich blood to the body) grows from both ventricles, rather than from the left ventricle only; and (4) a thickened muscular wall of the right ventricle, called right ventricular hypertrophy.

Transposition of the Great Arteries

A type of congenital heart defect that occurs when the two main arteries going out of the heart—the pulmonary artery and the aorta—are switched in position, or “transposed.”

Trisomy 21 (Down Syndrome)

Down syndrome is a condition in which a baby is born with an extra chromosome, chromosome 21. This extra copy changes the normal development of the body and brain and can cause developmental and physical problems for the baby.

Source: CDC Birth Defects Home Page, 2015

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