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Importance of Newborn Screening

All babies are screened, even if they look healthy, because some medical conditions cannot be seen by just looking at the baby. Finding these conditions soon after birth can help prevent some serious problems, such as brain damage, organ damage, and even death.

For example, a test for phenylketonuria (PKU) checks if the baby’s body can process phenylalanine. Phenylalanine is found in many protein-rich foods and some sweeteners and can build up in the blood and tissues of a baby with PKU, resulting in brain damage. This can be prevented if a baby with PKU is put on a special diet early. Babies are also tested for hypothyroidism, which means that their bodies do not make enough thyroid hormone. Babies with hypothyroidism can take medication with the hormone to avoid the slowed growth and brain damage that can happen if their hypothyroidism is not treated.

Even though some conditions cannot be treated as easily as PKU and hypothyroidism, it is still helpful to know about the condition as soon as possible. For example, a baby with sickle cell disease is at risk for harmful infections. These babies can take a daily dose of penicillin, an antibiotic medicine, to help prevent infections. Although the penicillin will not change the fact that the baby has sickle cell disease, it can help prevent serious problems.

CDC Expert Commentary on Medscape

Congenital Hypothyroidism (CH) Video

Watch this Medscape video to learn about CH and the importance of newborn screening.

When and How Babies are Screened

Ten Significant Public Health Achievements ― United States, 2001-2010: Newborn Screening

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Improvements in technology and endorsement of a uniform newborn-screening panel of diseases have led to earlier life-saving treatment and intervention for at least 3,400 additional newborns each year.

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Babies that are born in a hospital should be screened before they leave the hospital. Parents should take babies that are not born in a hospital or those that were not screened before leaving the hospital to a hospital or clinic to be checked within a few days of birth. In some states all babies are screened a second time, about two weeks after birth.

Blood Test

A health professional will take a few drops of blood from the baby’s heel. The blood sample is sent to a newborn screening lab for testing.

Hearing Screening

Hearing screening is a short test to tell if people might have hearing loss. Hearing screening is easy and not painful. In fact, babies are often asleep while being screened. All babies should be screened for hearing loss no later than 1 month of age. It is best if they are screened before leaving the hospital after birth.

Learn more about hearing screening »

Screening for Critical Congenital Heart Defects

Babies with a critical congenital heart defect (CCHD) are at significant risk of disability or death if their condition is not diagnosed soon after birth. Newborn screening using pulse oximetry can identify some infants with a CCHD before they show signs of the condition. Once identified, babies with a CCHD can be seen by cardiologists (doctors that know a lot about the heart) and can receive special care and treatment that can prevent disability and death early in life.

Many hospitals routinely screen all newborns for CCHDs. However, CCHD screening is not currently included in all state newborn screening panels.

Learn more about screening for CCHDs »

Conditions Tested

Each state runs its own newborn screening program. The conditions include sickle cell disease and other hemoglobin disorders, conditions where a child is unable to process certain nutrients (such as PKU), or conditions where there is a hormonal insufficiency (such as hypothyroidism). Most states screen for a standard number of conditions, but some states may screen for more. That means that there are differences in the screening process and the number and types of conditions included in screening in each state.

Baby’s First Test provides a current list of conditions included in newborn screening in each

Screening Results

If the results are "negative" ("pass" or in-range result) it means that the baby’s test results did not show signs of any of the conditions included in the screening.

If the results are "positive" ("fail" or out-of-range result) it means that the baby’s test results showed signs of one or more of the conditions included in the newborn screening. This does not always mean that the baby has the condition. It may just mean that more testing is needed.

The child’s doctor might recommend that the child get screened again or have more specific tests to diagnose a condition. For example, all babies who do not pass a hearing screening should have a full hearing test by three months and sometimes also at six months of age to confirm if there is a hearing loss.

Get Help!

If your baby’s newborn screening tests show that there could be a problem, work with your baby’s doctor to get any needed follow-up tests as soon as possible – don’t wait!

Finding and treating some of the conditions at an early age can prevent serious problems, such as brain damage, organ damage, and even death. Many of the conditions can be treated with medication or changes to the baby’s diet.

In order to make sure your baby reaches his or her full potential, it is very important to get help for any medical condition as soon as possible.