A birth defect is a physical problem that is present at birth (congenital). Birth defects may cause physical or mental problems, and some can be fatal. There are over 4,000 known birth defects. Other terms used for birth defects include congenital abnormalities, anomalies, and malformations.
Birth defects may be caused by inherited (genetic) problems or by environmental things such as exposure to certain toxic substances during pregnancy. Some birth defects can be linked to a direct cause. Other reasons are not as clear. More than 2 in 3 birth defects have no known cause.
Some birth defects are more common than others. The more common types are described below.
Cleft lip and cleft palate are problems of the mouth and lip. They affect about 1 in every 1,000 births. Cleft lip and cleft palate develop early in pregnancy when the sides of the lip and the roof of the mouth do not fuse together as they should. Cleft lip and cleft palate are caused by several genes inherited from both parents. They are also caused by environmental things that scientists don’t yet fully understand.
Cleft palate happens when the roof of the mouth does not completely close. This leaves an opening that can extend into the nasal cavity. The cleft may be on either side of the palate. It can extend from the front of the mouth (hard palate) to the throat (soft palate). Often the cleft will also include the lip. Cleft palate is not as noticeable as cleft lip because it is inside the mouth. It may be the only abnormality in the child. Or the child may also have cleft lip or other syndromes. In many cases, other family members have also had a cleft palate at birth.
Cleft lip happens when the lip doesn’t completely form in the womb (uterus). How serious the cleft lip is can vary greatly. The child may have a mild form, such as a notching of the lip. Or the child could have a severe form, with a large opening from the lip up through the nose. As a parent, you may find it stressful to adjust to the obvious problem of the face, because it is so easily noticed.
The most common problem with either defect is feeding your baby. Your baby may have problems sucking because his or her lips and roof of the mouth can’t close normally. You can use special nipples and feeding methods to help your baby get good nutrition. Cleft lip and cleft palate may also cause difficulties with speech and language because of the problems in the mouth. Other problems that are caused by these defects include ear infections and dental problems.
Treatment for cleft lip and cleft palate includes surgery. A cleft lip can be repaired within the first several months of life. Cleft palate repairs are usually done when the baby is 9 to 18 months old, but before the age of 2.
Clubfoot is a foot problem present at birth. It affects the bones, muscles, tendons, and blood vessels and can affect 1 or both feet. The foot is usually short and broad in appearance. The heel points downward, and the front half of the foot (forefoot) turns inward. The heel cord (Achilles tendon) is tight. The heel can appear narrow and the muscles in the calf are smaller, compared with a normal lower leg.
It occurs in about 1 to 3 in every 1,000 live births and affects boys twice as often as girls. Both feet are affected in 30% to 60% of all cases.
Many things may cause this birth defect. The cause may be genetic, but it usually isn’t known. Or it may be how the baby is positioned in the womb. Or it could be a combination of factors. Specific treatment will be determined by your child's healthcare provider. The goal is to straighten the foot so that it can grow and develop normally. Treatment for infants may include placing a series of casts on the foot to help stretch the soft tissues and return the foot to a normal position. Casting will correct clubfoot in most babies. Other babies may need surgery to help correct the position of the foot.
Hypospadias is a birth defect in which the male urine tube (urethra) opening is not located at the tip of the penis. With hypospadias, the urethral opening may be located anywhere along the urethra, but is most commonly along the underside of the penis near the tip. As the baby develops in the womb, the urethra doesn’t grow to its complete length. Also, the foreskin doesn’t develop completely. This can leave extra foreskin on the topside of the penis and no foreskin on the underside of the penis. The end of the penis may be curved downward.
Hypospadias is a disorder that occurs in about 5 out of 1,000 baby boys. Some baby boys who have other health problems like undescended testes or inguinal hernias may also have hypospadias. In very rare cases, a baby girl may have hypospadias. The opening of the urethra enters into the vagina.
Hypospadias can be repaired through surgery. Usually the surgical repair is done when the baby is 6 to 12 months old. At this time, the penis is not growing very much. At birth the baby should not be circumcised. This is because the extra foreskin may be needed for the surgery.
Developmental dysplasia of the hip (DDH) is a condition of the hip joint that is present at birth. It occurs in 1 to 2 of every 1,000 live births. The hip joint is created as a ball and socket joint. In DDH, the hip socket may be shallow. This lets the "ball" of the long leg bone (femoral head) slip in and out of the socket. The "ball" may move partially or completely out of the hip socket. Many things may cause this birth defect. Both genes and the environment may be part of the cause. All newborn babies are screened in the hospital for this hip problem before they go home. But because DDH may not be discovered until later, they will also be screened at their regular checkups after leaving the hospital.
The goal of treatment is to put the femoral head back into the socket of the hip so that the hip can develop normally. Treatment for infants may include having the baby wear a special harness to hold the hips in place. Or the baby may be placed in a cast. Some babies may need surgery.
Congenital heart defects are problems in the baby’s heart structure and function. Often a defect affects how blood flows through the heart and out to the body. The defects can range from mild to severe.
They are likely caused by a combination of genes and things in the environment. Congenital heart defects are the most common type of birth defect in the U.S. They affect about 8 of every 1,000 babies.
Some congenital heart defects don’t need to be treated. Some people with heart defects will just be monitored throughout their life. Sometimes, a child may need surgery to repair a defect. This may be needed right away after birth or later in life if complications develop.
Neural tube defects are a group of disorders that occur early in the development of the baby in the womb. They happen when the neural tube doesn’t form correctly. The neural tube is a group of cells in the embryo that will become the spinal cord and the brain, and the bone and tissues around them. In open neural tube defects, the tube doesn’t close fully. The spinal cord and tissues are left exposed. The most common form of this defect is spina bifida (myelomeningocele). Babies with neural tube defects may have nerve damage and paralysis. In another type, the brain and skull do not develop (anencephaly). Babies with anencephaly do not survive.
There is no cure for neural tube defects. Treatment for affected babies depends upon the type of defect and how serious it is. Women can help prevent neural tube defects by taking 400 mcg of folic acid before and during pregnancy. This is the amount usually found in prenatal vitamins.