9 Birth Defects that Can Occur in Babies

About 1 in every 33 babies—or 3%— in the U.S. is born with a birth defect, according to the Centers for Disease Control and Prevention (CDC). The impact of a birth defect on your child and family will vary; some birth defects are minor and treatable, while others will be more severe and could impact many different aspects of your child's life.

While birth defects can happen, not every family is prepared for what can happen if their child is diagnosed with a birth defect and that's okay. There are resources available to help.

The first thing you should do if your child is diagnosed with a birth defect is get a second (or more) opinion. Start with your pediatrician or obstetrician, who can refer you to appropriate specialists. Some birth defects may be diagnosed before your baby is even born, while others may not be apparent until after birth, so in addition to appointments with specialists, you should also keep up with regularly scheduled well-baby visits, because many birth defect complications can be treated through early detection and intervention.

No matter what diagnosis your baby might have, finding out you are facing a birth defect can be a challenge. Here is some more information on what birth defects are most common in the U.S. and what might happen if your baby is born with a birth defect.

1. Congenital Heart Defects

How often they occur

Congenital heart defects occur in about 1 in 110 births and have a variety of causes, including genetic abnormalities or a mistake during fetal development. Some may be so mild that they have no visible symptoms.

How they are diagnosed

In such cases the doctor usually discovers the problem when they detect an abnormal heart sound—called a murmur—during a routine examination. Some murmurs are meaningless; further tests are usually required to determine whether your baby's is due to a heart defect. Serious heart defects are outwardly detectable and, if left untreated, can cause congestive heart failure, in which the heart becomes incapable of pumping enough blood to the lungs or other parts of the body.

Symptoms

Rapid heartbeat; breathing difficulties; feeding problems (which result in inadequate weight gain); swelling in the legs, abdomen, or the eyes; pale grey or bluish skin. Sometimes, the symptoms of a heart defect will become apparent in the hospital shortly after birth, so be sure to ask your baby's nurse if you have any concerns. Others may not become noticeable until your baby gets older.

Treatment

Most heart defects can be corrected or at least improved through surgery, drugs, or a mechanical aid like a pacemaker.

2. Clubfoot

How often it occurs

Clubfoot occurs in approximately 1 in 1,000 newborns—affecting males about twice as often as females—and includes several kinds of ankle and foot deformities. The exact cause of clubfoot isn't clear, but it's probably a combination of heredity and environmental factors that affect fetal growth.

Symptoms

Clubfoot can be mild or severe and can affect one or both feet. Mild clubfoot is not painful and won't bother the baby until they begin to stand or talk.

Treatment

For a mild case, treatment starts immediately after diagnosis and involves gently placing the foot into the correct position and helping the child do special exercises. Often, however, the baby needs more specialized treatment, such as plaster casts, bandaging with splints followed by time in special shoes, or surgery followed by exercises. The process may take three to six months, which checkups for several years after.

3. Cleft Lip or Palate

How often it occurs

About 1 in every 1,600 babies is born with a cleft lip with cleft palate in the U.S. Cleft lip or palate appears most often in people of Asian and Hispanic descent, as well as among certain groups of Native Americans. It is seen less frequently among Black people.

Causes

The exact cause is hard to determine, but it's likely that genetic and environmental factors interact to prevent either the hard palate (the roof of the mouth), the soft palate (the tissue at the back of the mouth), or the upper lip, all of which normally are split early in fetal development, from closing.

Symptoms

The cleft can be mild (a notch on the upper lip) or severe (involving the lip, the floor of the nostril, and the dental arch). A child with a cleft palate usually needs a speech pathologist. Language development can be affected not only by the structure of the lip and palate but also by the side effects of middle-ear infections, which are common in babies and toddlers with this defect (probably because their ears don't drain properly).

Babies with a cleft palate may also need help with feeding. (Those with a cleft lip generally don't have problems in this area.) Because they have trouble sucking, they must be fed in a sitting position with a special bottle. Depending on the severity of the condition, parents who breastfeed may have to express milk and bottlefeed baby until the cleft is repaired.

Treatment

Surgical repair for a cleft lip should be done by about 3 months of age. Surgery to repair a cleft palate, which restores the partition between the nose and the mouth, is usually done later—between 6 and 12 months of age—to allow for growth of the child's face. Though follow-up treatment is sometimes necessary, repair of a cleft lip or palate almost always leaves the child with only minimal scarring.

4. Spina Bifida

How often it occurs

About 1,400 babies are born with spina bifida in the U.S. every year.

Causes

There is no one known cause of spina bifida. The condition is thought to be caused by a malformation of a neural tube (the embryonic structure that develops into the brain and spine) that prevents the backbone from closing completely during fetal development. Some cases of neural-tube defects can be detected through tests given to the pregnant person during pregnancy. When one is suspected, the baby usually is delivered by cesarean section so specialists can be on hand during and after the birth.

Symptoms

Spina bifida ranges in severity from practically harmless to causing leg paralysis and bladder and bowel control problems.

Treatment

In the most severe cases, the baby is operated on within 48 hours of birth (or in-utero through a new technique that is not yet widely available). Parents then learn how to exercise the baby's legs and feet to prepare them for walking with leg braces and crutches. Some children will eventually need to use a wheelchair and work with specialists in orthopedics and urology.

5. Missing or Undeveloped Limbs

Causes

Unfortunately, the cause of this birth defect is largely unknown. Some experts believe that exposure during pregnancy to a chemical or virus that only mildly affects the pregnant parent might be possible causes.

Treatment

When a child is born with a limb anomaly, the doctor refers the parents to an orthopedic specialist and a physical therapist. The child is then fitted with a prosthesis (artificial body part) as soon as possible so that they become comfortable with it early on. They will also undergo physical therapy to learn how to use the prosthesis much as other children learn to control their body parts.

6. Sickle-Cell Disease

Prevalence

Sickle-cell disease occurs in around 1 in 625 births, mostly affecting Black people and and Hispanic people of Caribbean ancestry.

How doctors find it

Because of its prevalence, 30 states require that newborns be given the blood test that detects the disorder.

Symptoms

The disease can cause debilitating bouts of pain and damage to vital organs and can sometimes be fatal. Sickle-cell disease affects the hemoglobin (a protein inside the red blood cells) in such a way that the cells become distorted: Instead of their normal, round shape, they look like bananas or sickles (hence the name).

These misformed cells then become trapped in and destroyed by the liver and spleen, resulting in anemia. In severe cases, an affected child may be pale, have shortness of breath, and tire easily. The episodes of pain, called crises, happen when the cells become stuck, blocking tiny blood vessels and cutting off the oxygen supply to various parts of the child's body.

Another complication of sickle-cell disease, noticeable mostly in infants and young children, is vulnerability to severe bacterial infections. Two weapons against this risk are immunization (the usual vaccines, as well as pneumonia and flu shots) and daily preventative penicillin treatments.

Treatment

Although the disease can't be cured, a number of new therapies that reduce the severity and frequency of crises are being studied.

7. PKU (Phenylketonuria)

Prevalence

PKU (phenylketonuria) is an inherited metabolic disorder that occurs in 1 in 15,000 births (less commonly among Black people and people of Jewish descent).

Detection

All babies in the U.S. are tested for the disease soon after birth.

Symptoms

A child with PKU is missing a crucial enzyme that breaks down a protein called phenylalanine that is found in many goods. If PKU is left untreated, this protein can rise to high concentrations in the body and cause developmental disabilities.

Treatment

Children born with PKU will need to follow a special diet. Usually started before the fourth week of life, this diet is low in foods that contain phenylalanine, including breast milk and cow's milk. Because of that restriction, an affected child must be fed a special formula. As the baby gets older, they can eat certain vegetables, fruits, and grain products but usually must avoid cheese, meat, fish, and eggs. Regular blood tests of phenylalanine levels can help determine what an affected child can and can't eat.

8. Down Syndrome

How often it occurs

Down syndrome occurs in about 1 in 700 births in the U.S.

Symptoms

A child with Down syndrome generally has distinct physical features, including slanted eyes; small ears that fold over at the top; a small mouth, which makes the tongue appear larger; a small nose with a flattened nasal bridge; a short neck; and small hands with short fingers. More than 50% of children with Down syndrome also have visual or hearing impairments. Ear infections, heart defects, and intestinal malformations are also common among children with this defect.

Most children with Down Syndrome will be able to meet many developmental milestones, such as walking, talking, and being toilet trained—although generally they learn how to do so later than unaffected children.

9. Fragile X Syndrome

Prevalence

Fragile X syndrome primarily affects males (about 1 in 4,000 to 7,000). Although 1 in 1,000 females is a carrier, only one in three shows outward signs of having the defect, including intellectual impairment. The range of disability varies from mild to severe.

Symptoms

The physical characteristics of Fragile X syndrome may include large ears, an elongated face, poor muscle tone, flat feet, large testicles, overcrowded teeth, cleft palate, heart problems, and symptoms that resemble autism. Affected children may also suffer seizures. However, many children with Fragile X syndrome appear to be physically normal at birth, so a diagnosis may not be made until the ages of 18 months and 2 years. At that time, a lack of language development coupled with other developmental delays usually prompts testing.

Treatment

As with Down syndrome, children with Fragile X syndrome can be expected to do most things that any young child can do, although they also generally learn these things later than unaffected children. And, as with most of these birth defects, early-intervention programs begun in infancy can help maximize the child's development.

Richard B. Johnston Jr., MD, FAAP, is an Emeritus Professor of Pediatrics at the University of Colorado School of Medicine and National Jewish Health.