Newborn screening programs across the United States currently screen 4 million infants each year. This public health program detects treatable disorders in newborns, allowing treatment to begin often before symptoms or permanent problems occur. Newborn screening not only saves lives, but can also improve the health and quality of life for children and their families.

Within the first 24 to 48 hours after birth, babies undergo a simple heel stick and a few drops of blood are collected on a special paper card. Health care providers then test those blood spots for a number of congenital disorders (conditions that are present at birth). Infants are also screened for hearing disorders and for other serious heart problems using methods other than dried blood spots.

When a screen is positive for any condition, the newborn's parents are informed that their infant has an "out-of-range" test result for one of the conditions. But a positive screening test does not mean the infant has a disorder. Additional testing is needed to confirm and diagnose the condition.

Only about one out of 300 newborns is later diagnosed with a treatable condition. Once the condition is confirmed, the infant is referred to an appropriate specialist so that treatment can begin as early as possible.

Newborn screening is a set of laboratory tests performed on newborn babies to detect a set of known genetic diseases. Typically, this testing is performed on a blood sample obtained from a heel prick when the baby is two or three days old. In the United States, newborn screening is mandatory for a defined set of genetic diseases, although the exact set differs from state to state. Newborn screening tests focus on conditions for which early diagnosis is important to treating or preventing disease.

Newborn genetic screening. Mandatory newborn screening programs are a classic public health success story. These programs save lives and prevent disability in thousands of infants every year by identifying certain conditions promptly after birth. Early detection of those conditions allows different kinds of treatments and interventions to be provided very early in a newborn's life when it can really make a difference in health outcomes and even help to prevent severe, irreversible disability. The reason why some states include different tests in their screening programs is complicated. A decision has to be made about what test to include based on which ones will bring about the best health outcomes for newborns. The decision-makers also have to consider the costs and feasibility of screening, diagnosis and treatment and weigh that against the potential health benefits of each test.

Newborn screening tests use a dried blood sample collected during the first week after birth to measure the presence of disease biomarkers (a measurable substance or characteristic that is indicative of a disease).

What is newborn screening?

Newborn screening in the United States is a major public health success that has saved countless lives. Each state runs its own newborn screening program, where almost all newborns are tested for at least 30 (and in some states more than 50) serious-but-treatable conditions that occur during childhood.Almost all of the current newborn screening tests use a dried blood sample collected during the first week after birth to measure the presence of disease biomarkers (a measurable substance or characteristic that is indicative of a disease). Currently, the tests used by state newborn screening programs are fast, low cost and accurate in identifying disease before symptoms appear.

How does genomics come into it?

The cost of genome sequencing has now decreased to a price range similar to many other complex medical tests, increasing the possibilities for its clinical application. One potential use for genome sequencing would be to replace or supplement the existing traditional panels of newborn screening tests. Sequencing a newborn's genome could provide more health information than the current panel of tests, and could potentially be used to guide an individual's lifetime of medical care, providing early information on both treatable childhood diseases and conditions that occur in adulthood.

Many questions remain to be answered before contemplating a future of routine newborn genome sequencing. Among the questions are:

• Can DNA sequencing identify the same conditions at birth with as much accuracy and speed as traditional methods?

• Is having a genome sequence from birth useful for that individual's clinical care?

• What if the genome sequence reveals information about untreatable diseases, or even conditions that will not occur until adulthood?

• What is the risk to newborns that the identification of specific genetic variants, such as a predisposition to a disease, could lead to future discrimination?

• How might the use of genome sequencing affect public support for newborn screening programs?

• How feasible would it be for states to perform genome sequencing in addition, or instead of, existing testing programs?

• Are there additional considerations to collecting and storing newborn genome sequences versus newborn blood specimens?

Clinicians, scientists, bioethicists and others have debated these issues for several years but, until now, they have been abstract questions.Thanks to a new research program being funded by the National Institutes of Health, a small number of pilot studies are beginning to carefully examine these questions. The program's goal is to generate scientific evidence and ethical considerations that healthcare professionals and policy makers can use to formulate future practical applications and policies related to the use of genome sequencing in the newborn period.

Is the government planning to replace newborn screening with newborn genome sequencing?

No. This research effort seeks to determine whether or not genome sequence data could provide additional information that would be of benefit to newborns and their families during the newborn period.

What about the emotional toll on families who receive information about mutations with health consequences?

Studying the ethical, legal, and social implications of receiving genomic information about newborns is an integral component of this research program. While there have been discussions in the abstract about how families will process positive diagnoses, until now these issues have not been studied in depth. There is precedence for this approach. In the abstract, many experts believed that informing someone that they had an increased risk of developing Alzheimer's disease (which is untreatable) would cause severe psychological distress. Therefore, NIH funded the REVEAL and REVEAL II studies to explore whether these assumptions were true. Surprisingly, the results of those trials suggested that individuals are not unduly distressed, demonstrating the value of such research. It is important that we seek understanding of what, if any, impacts genome sequencing and similar information could have in this possible scenario.

What protections are in place for families who do not wish to receive this information?

Participation in NIH research is entirely voluntary. Participants will only be enrolled in the studies after participating in an informed consent process, where they will be educated about the goals of the study and the possible outcomes. While in some cases it may be possible to participate in a particular aspect of a study without receiving research results, one aim of the program is to determine how clinicians and families use genomic sequence information in decision-making. Several of the funded projects are specifically interested in how families understand and respond to genomic information (including optimal ways to communicate that information). Therefore participation in these research studies may not be suitable for families who do not wish to know what their sequence information contains. As with all federally funded biomedical research studies involving human research participants, the research is overseen by an Institutional Review Board at each institute, which monitors the study plans and implementation to ensure ethical conduct throughout the research process.

The timing of newborn screening (NBS) is very important. Babies need screening during the first few days of life, because some of the conditions found by screening require treatment or intervention right away.

NBS happens after birth, usually when your baby is between 24 and 48 hours (1 and 2 days) old. If a baby is tested before 24 hours, they may need to be retested.

Some babies who have had treatments such as transfusions or dialysis may be tested later or may need further testing after their blood has returned to normal. In addition, babies who are born too early, or who receive nutrients or medicines before screening, may need further testing.

There are two models that states use to screen all newborns: the one-screen model or the two-screen model.

• Most states use the one-screen model. In this model, babies are screened only once when they are 24 to 48 hours old. This one screen looks for all conditions on the state’s newborn screening panel.
• Thirteen states use the two-screen model. In this model, all babies are screened at 24 to 48 hours old and screened again at 1 to 2 weeks old. The second screen usually happens in a health care provider’s office as part of a well baby visit.
• States choose the one-screen model or the two-screen model based on many factors. These factors can include historical practice in the state or the testing cut-offs (guidelines to decide if a baby needs follow up) the state uses. In either model, all babies are screened for all of the conditions that their state requires.
• Whether you live in a one-screen or two-screen state, your baby may need additional screening and follow up based on their newborn screening results.

All babies need NBS, regardless of where they are born.

If your baby is born at a hospital, screening will happen before you take your baby home. Usually, a health care provider performs NBS in your room or a newborn/nursery area.

If your baby has an out-of-hospital birth, screening can happen outside of the hospital like at your birth center or home. Many midwives are trained to complete NBS.

If you are planning an out-of-hospital birth, talk to your midwife about NBS before your baby is born. If your midwife cannot perform NBS, make other arrangements. Your baby’s health care provider can help arrange screening by another midwife, a hospital, clinic, or local health department. It is important that you make a plan so your baby completes screening near the recommended age.

Newborn screening usually starts with a blood test, followed by a hearing test and possibly other tests.

First, hospital staff fill out a newborn screening card with the infant’s vital information—name, sex, weight, and date and time of birth—and the date and time of the blood collection. Part of the card consists of special absorbent paper used to collect the blood sample.

After warming and careful sterilizing of the infant's heel, medical staff do a "heel stick," in which they make a small puncture in the baby's heel and squeeze out a few drops of blood. They put the absorbent part of the card in contact with the blood drop. They continue until all the printed circles on the card contain a blood sample.

The card is then sent to a laboratory, where the blood is tested for the various conditions as part of the newborn screening panel.

Hearing Test

Hospital staff typically use one of two methods for the hearing test. Both are quick (5 to 10 minutes) and safe.

• Otoacoustic (pronounced oh-toe-uh-KOO-stik) emissions (OAE). This test determines if certain parts of the infant’s ear respond to sound. A miniature earphone and microphone are placed in the ear, and sounds are played. If the infant has normal hearing, the microphone picks up an echo reflected back into the ear canal. Failure to detect an echo means there may be a loss of hearing.
• Auditory brain stem response (ABR). This test evaluates the auditory brain stem—the part of the auditory nerve that carries sound from the ear to the brain—and the brain’s response to sound. Miniature earphones are placed in the ear, and sounds are played. Electrodes (small, sticky electric conductors) are placed on the infant’s head to detect the brain’s response to the sounds. If the infant’s brain does not respond consistently to the sounds, there may be a hearing problem.

Pulse Oximetry

In some cases, hospital staff will perform pulse oximetry (pronounced ox-EM-i-tree) to measure how much oxygen is in the infant's blood. Pulse oximetry is usually performed at least 24 hours after birth. Hospital staff place a sensor on the infant's skin for a couple of minutes, and the sensor measures the level of oxygen in the blood through the skin.

Low blood oxygen can indicate that a newborn has heart problems. Pulse oximetry can help identify infants with a condition called critical congenital heart disease (CCHD). According to the Centers for Disease Control and Prevention, 25% of babies with congenital heart disease (one that is present at birth) have a CCHD. There is evidence that medical care is allowing more infants with CCHD to survive. One study found that 83% of infants with a CCHD who were born between 1994 and 2005 survived at least 1 year. Only 67% of infants born between 1979 and 1993 with a CCHD lived to 1 year.

Other Blood Tests

Some states require a second blood test that repeats the initial set of screenings.

• The first screening is performed 24 to 48 hours after the infant is born, ideally before the infant leaves the hospital. For some conditions, the screening is not valid if the blood is taken within 24 hours of birth.
• The second screening is performed when the infant is 10 days to 2 weeks old to ensure that the health care provider has the most accurate results possible.

Blood spot screening (sometimes called the “heel stick” or “24-hour test”) uses a few drops of blood from your baby’s heel to determine if your baby might have one of many serious conditions. Even though some health care providers still refer to blood spot screening as the “PKU test,” this term is no longer accurate because NBS now checks for many conditions.

Following is a step-by-step guide explaining how blood spot screening happens:

• Between 24 and 48 hours after birth, a health care provider will tell you that it is time for your newborn’s blood spot screening.
• Your baby can stay swaddled during blood spot screening.
• To make the process easier, the health care provider will gently warm your baby’s foot to increase blood flow.
• The health care provider will then make a quick pinprick on your baby’s heel. Your baby may feel the prick and start to cry, but it will be over very quickly and will not leave a mark.
• The health care provider will collect a few small drops of blood from your baby’s heel, then drop them onto small circles on a special card.
  • The part of the card with the circles contains a type of paper called filter paper. This paper absorbs the blood drops.
  • The other part of the card has information about your baby. This information tells whose blood is on the card and how to reach you and your baby’s health care provider.
• Once the blood spots have dried, the card is sent off to a laboratory. There, the staff runs laboratory tests looking for signs of certain serious conditions. Each state has its own newborn screening panel, which is a list of the conditions that the state checks during NBS. To see the newborn screening panel for your state, visit the State pages.

Results from blood spot screening are usually ready in about five to seven days. The public health laboratory sends your baby’s results to your baby’s health care provider, not straight to you. If the result suggests the presence of a condition, then either the health care provider or the state NBS program will contact you.

Be sure to ask about your baby’s results at your baby’s first or second well-child visit. It is important to ask about your baby’s NBS results—do not assume that no news means that the results are in-range.

Pulse oximetry screening uses a sensor to determine if your baby might have certain heart conditions called critical congenital heart disease (CCHD).

CCHD is a group of serious heart conditions present at birth. Children with CCHD have any of a wide range of heart problems that arise when parts of the heart do not form correctly.

In some forms of CCHD, the heart has trouble delivering oxygen from the lungs to the rest of the body. Babies with these forms of CCHD have low levels of oxygen in their blood. Measuring your baby’s blood oxygen level can help see if your baby needs urgent heart treatment.

Following is a step-by-step guide explaining how pulse oximetry screening happens:

• Between 24 and 48 hours after birth, a health care provider will tell you that it is time for your newborn’s pulse oximetry screening.
• The health care provider will place a small wrap on your baby’s skin, usually around the right hand or wrist and on either foot. One side of the wrap has a light, and the other has a sensor.
• The health care provider will connect the wrap to a monitor that uses the sensor’s reading to calculate how much oxygen is in your baby’s blood. Using the numbers on this monitor, the health care provider can tell whether your baby might have CCHD.
• Babies who do not pass pulse oximetry screening the first time may repeat it or may need further testing.

Results from pulse oximetry screening are ready as soon as the screening is done.

If your baby does not pass pulse oximetry screening, a health care provider may recommend more testing to see if your baby’s heart and lungs are working well. This testing can involve an echocardiogram, electrocardiogram, and/or chest X-ray, which is usually done right away.

Your baby’s health care provider will help decide what test(s) your baby needs.

Newborn hearing screening uses earbuds or earphones to check your baby’s hearing.

Babies do not usually start talking until they are about 1 year old, but language begins developing at birth. Babies learn sounds, speech, and language by hearing people speaking around and to them during the first months of life.

A child who has even a mild hearing loss may be slow to learn words and how to communicate if not helped early. Newborn hearing screening is important because it finds children that may need help as early in their lives as possible.

Following is a step-by-step guide explaining how newborn hearing screening happens:

• Hearing screening usually happens any time after your baby is 12 hours old. Around or after this time, a health care provider will tell you that it is time for your newborn’s hearing screening.
• Hearing screening works best when your baby is calm and in a quiet room. You may be asked to hold your baby during screening, or your baby may stay swaddled.
• There are two types of hearing screening. Your baby might have one or both types. Both types work similarly and are quick and safe.
  • Otoacoustic emissions (often called “OAE”): In this screening, a health care provider places a small ear bud in each of your baby’s ears. The ear buds play soft sounds for your baby. The ear buds are connected to a computer that measures how the ear responds to the soft sounds. If your baby’s ears are working as they should, the computer will detect a response. If your baby is deaf or hard of hearing, the computer will not detect a response.
  • Automated auditory brainstem response (often called “AABR”): In this screening, a health care provider places earphones over your baby’s ears and small sensors that look like band-aids on your baby’s head and neck. The earphones play soft sounds for your baby. The sensors measure how your baby’s ears and brain respond to the sounds and then send this information to a computer. If your baby can hear typically, the computer records a response to the sounds. If your baby is deaf or hard of hearing, the computer records either a very small response or no response at all.
• Your baby may not pass screening if your baby is deaf or hard of hearing in one or both ears, if there is fluid in the ear, or if there is too much noise during screening (for example, from movement or crying).

Results from hearing screening are ready as soon as the screening is done.

If your baby does not pass the hearing screening, resulting in a “fail,” you will be referred to a specialist for more evaluation and testing of your baby’s hearing. This second check usually happens one to two weeks after the first screening.

Many parents have questions about NBS. Following is a list of questions that you may want to ask your health care provider or your baby’s health care provider before your baby’s birth, before your baby’s screening, or while your baby is being screened.

• Will I need to ask for my baby to be screened?
• When does NBS happen?
• Can I be with my baby during screening?
• How are the costs of newborn screening covered?
• For what conditions will my baby be screened?
• What options do I have for NBS?
• How long will it take to get my baby’s results?
• How will I get my baby’s results?
• When will the results be in my baby’s medical chart?
• What will happen if my baby’s tests are out-of-range?
• Who can I contact if I have more questions?

The Advisory Committee on Heritable Disorders in Newborns and Children (ACHDNC) issues a Recommended Universal Screening Panel (RUSP) that identifies a number of core conditions—those for which screening is highly recommended—and secondary conditions, for which screening is optional. As of November 2016, the RUSP included 34 core conditions and 26 secondary conditions.

What are some examples of newborn screening successes?

Many conditions included in today's U.S. newborn screening programs no longer cause serious disability or illness because they are detected early and treated immediately—but they once did. The three examples that follow are conditions that cause serious developmental and intellectual disabilities, or death, if they are not detected and treated early. Successful newborn screening for these conditions and follow-up treatment means that babies who might have died or needed specialized long-term care, can now grow into healthy adulthood.

Severe Combined Immune Deficiency (SCID)

One of the newest additions to the RUSP is an inherited condition, called SCID , that makes a child’s body unable to fight off even mild infections. The condition, also known as “bubble boy syndrome,” causes parts of the immune system to not work properly. If untreated, infants with SCID are unlikely to live past the age of 2 years. However, when SCID is detected and treated early, children can live longer, healthier lives.

SCID is rare, with between 40 and 100 infants diagnosed each year in the United States. Because SCID is a newcomer to the RUSP, not all states screen for it yet, meaning infants with the condition might be getting sick without being diagnosed.

Infants should be evaluated for SCID and other types of immune system problems if they have:

• A high number of infections
• Infections that do not improve with antibiotic treatment for 2 or more months
• Diarrhea
• Poor weight gain or growth (called “failure to thrive”)
• Fungal infections in the mouth (called “thrush”) that will not go away

An infant with any of these warning signs should be tested for SCID as soon as possible.

Phenylketonuria (PKU)

PKU (pronounced fee-nill-key-toe-NURR-ee-uh) is a metabolic disorder that is detected by newborn screening. In PKU, the body cannot digest or process one of the building blocks of proteins, an amino acid called phenylalanine (pronounced fen-l-AL-uh-neen), or Phe (pronounced fee). Phe is found naturally in many foods, especially high-protein foods.

PKU was the first condition for which a screening test was developed, and the first condition for which widespread newborn testing was implemented in the 1960s.

If PKU is left untreated, the Phe builds up in the body and brain. By 3 to 6 months of age, infants with untreated PKU begin to show symptoms of intellectual and developmental disability. These disabilities can become severe if Phe remains at high levels.

Fortunately, PKU is treatable. The treatment consists of a diet containing little or no Phe and higher levels of other amino acids. If children with the condition are placed on this diet at birth, they grow normally and usually show no symptoms or health problems. NICHD-sponsored research has shown that people with PKU should stay on the restricted diet as they enter adulthood and, in fact, throughout their lives. This is especially important for women of childbearing age who wish to or who might become pregnant.

Before newborn screening programs could detect PKU in the first few hours after birth, PKU was one of the leading causes of intellectual and developmental disabilities (IDD) in the United States. Today, as a result of newborn screening programs that allow for almost immediate treatment of the condition, PKU has been virtually eliminated as a cause of IDD in this country.

Galactosemia

Another metabolic disorder included in newborn screening is galactosemia (pronounced guh-lak-toe-SEE-me-uh), which means being unable to use galactose (pronounced guh-LAK-tohs). Galactose is one of two simple sugars that make up lactose, the sugar in milk. People with galactosemia cannot have any milk or milk products.

If someone with galactosemia consumes milk or milk products (human or animal), the galactose builds up in their blood and causes serious damage to their liver, brain, kidneys, and eyes. Infants with untreated galactosemia can die of a serious blood infection or of liver failure. Those that may survive usually have IDD and other damage to the brain and nervous system. Even milder forms of galactosemia still require treatment to prevent early cataracts, an unsteady gait, and delays in learning, talking, and growth.

The treatment for galactosemia is not to consume any milk or milk products and to avoid other foods that contain this sugar. If this disease is diagnosed very early and the infant is placed on a strict galactose-free diet, she or he is likely to live a relatively normal life, although mild IDD may still develop. If not placed on a galactose-free diet immediately, an infant will develop symptoms in the first few days after birth.

Before it could be detected either before birth or through a newborn screening program, galactosemia was a frequent cause of IDD and early death. Oregon began screening newborns for galactosemia 50 years ago, and all states now screen for this condition. Screening has identified more than 2,500 infants with the condition, many of whom would have died without the screening.

No.

Even though every state in the U.S. requires NBS, each state manages its own NBS program. This means that NBS can be a little different in each state.

For example, some states may give parents different options during screening, have different NBS costs, or look for different conditions during screening. It is important to be familiar with how NBS works in your state.

Parent Options During Screening

States give parents options during NBS. Examples of choices that differ by state include the following:

• Whether and how to refuse NBS—All states require NBS, but most states let parents refuse screening for their baby. Accepted reasons for refusal depend on the laws in a state. For example, some states only let parents refuse NBS for religious reasons. Other states let parents refuse for any reason. A couple of states do not allow parents to refuse NBS at all.
• What happens with your newborn’s blood spots after NBS—Some states give parents choices about what happens to their baby’s dried blood spots after screening is complete. For example, some states let parents choose whether the blood sample is stored, destroyed, or used for research studies.

You can find out about parent options in your state by contacting your state’s newborn screening program.

Differences in the Newborn Screening Panel

The group of conditions that a state has chosen to detect with newborn blood spot screening is called its newborn screening panel. In the U.S., each state decides which conditions to include on its newborn screening panel. This means that babies in different states may be screened for slightly different panels of conditions.

States consider many things when deciding which conditions belong on their newborn screening panels. For example, all core conditions on state newborn screening panels:

• Have a low-cost screen
• Cannot be found just by looking at a baby
• Are serious and, without treatment, cause serious health problems early in life
• Have health care providers with the right expertise to diagnose, treat, and care for babies with the conditions
• Have an effective treatment

To help states decide which conditions to include on their newborn screening panels, the U.S. Secretary of Health and Human Services provides a list of conditions recommended for newborn screening. This list is called the Recommended Uniform Screening Panel (RUSP).

To learn more about the RUSP, visit the Recommended Uniform Screening Panel page.

In most cases, parents don't hear anything at all about the results of their baby's newborn screening tests. This usually means that the tests did not detect any of the conditions screened for—or, as the child's health care provider might say, the results were "negative" or "in-range." Parents with concerns should talk with their health care provider and ask about the results.

Most states notify parents only when the results are "positive" or "out of range" for a particular condition(s).

Out of Range Results

If the screening detects one or more conditions, the result is "positive" or, more accurately, "out of range." The child's health care provider or someone from the state health department will notify the parents, usually within 2 to 3 weeks, if the results are out of range.

This result does not mean the child definitely has the condition detected. Sometimes, the tests produce a "false positive," meaning that even though the test result was positive, the infant does not actually have the disease.

If the test result is positive, it is very important for the infant to undergo additional testing right away to confirm and diagnose any specific condition(s). Screening tests and diagnostic tests are not the same. If a baby is diagnosed with a condition, his or her health care provider and other providers will recommend a course of treatment.

The Importance of Following Up

Newborn screening is used to detect serious medical conditions. If not treated, some of these conditions can cause lifelong health problems; others can cause death.

If your child’s health care provider or the state health department calls you about your infant’s newborn screening results, it is important to follow up quickly. Follow their instructions to get care for your baby.

Newborn screening makes early diagnosis possible so that treatment can begin immediately—before serious problems can occur or become permanent. This approach helps to ensure the best possible outcomes for babies.

The results of your baby’s newborn blood spot screening become available five to seven days after birth. Three types of results are possible:

• In-range (also called negative, normal, or low risk)
• Out-of-range (also called positive, abnormal, or high risk)
• Borderline (also called inconclusive or medium risk)

In-Range Screening Results

What Does an In-Range Result Mean?

An in-range result means that your baby probably does not have a condition detected by blood spot screening. Babies with in-range results do not need more testing.

Your baby’s health care provider may tell you about in-range results at your baby’s first or second well-child visit. If you do not receive your baby’s results, be sure to ask about them so that you know screening was completed.

Health care providers might also refer to in-range results as “negative,” “normal,” or “low risk.”

Can My Baby Have an In-Range Result and Still Have the Condition?

Yes. Sometimes, when NBS shows that a baby is unlikely to have a condition, the baby in fact has that condition. When screening “misses” a baby with the condition, it is called a false-negative result.

Health care providers usually catch false-negative results when a baby begins having symptoms of the condition. Any baby who starts having health problems (like trouble breathing, slow weight gain, or problems with movement) needs more testing—even if that baby’s blood spot screening results were in-range. Regular checkups are important to make sure your baby is healthy and growing normally.

Whenever you have concerns about your baby’s health, you should contact your baby’s health care provider right away.

Out-of-Range Screening Results

What Does an Out-of-Range Result Mean?

An out-of-range result means that your baby might have the condition detected by the screening test. Babies with out-of-range results need more testing.

Your baby’s health care provider will contact you to tell you about out-of-range results and any next steps you should take. If your baby has an out-of-range result, it is important to follow all of your health care provider’s directions about what to do next.

Usually, the health care provider will help you make an appointment for more testing with a specialist. Your baby may need to see the specialist and have any recommended testing right away to diagnose the condition.

You should follow your health care provider’s recommendations about when and what kind of testing your baby needs. To be safe, your health care provider may also recommend that your baby begin treatment for the condition right away.

Health care providers might also refer to out-of-range results as “positive,” “abnormal,” or “high risk.”

Do All Babies With Out-of-Range Results Have the Condition?

No. Sometimes, when NBS shows that a baby might have a condition, further testing reveals that the baby does not have the condition at all. This is called a false-positive result. Health care providers usually determine false-positive cases during follow-up testing.

False-positive results can happen in blood-spot screening for many reasons, like the following:

• A reason other than the screened condition—Newborn screening uses indicators in the blood to check whether your baby might have certain conditions. However, other things that have nothing to do with the NBS conditions (for example, stress) can also affect these indicators. Therefore, an out-of-range result can either mean that your baby has an NBS condition or that something else is affecting the result of the screen.
• A problem with how or when your baby’s blood was screened—Collecting and processing NBS blood samples need to happen in a very precise way. If they do not happen correctly, your baby may receive a false-positive result. This might happen if:
  • Your baby’s screening was done outside the recommended time frame
  • Your baby’s blood sample was not collected correctly
  • The card with your baby’s blood sample got scratched or stained by something other than your baby’s blood
  • The blood sample was stored incorrectly
  • The information on the screening card was wrong

If your baby has a false-positive result, your baby does not have and will not develop the condition.

Borderline Screening Results

A borderline result means that your baby’s screening results fall somewhere between an in-range and out-of-range result.

Babies with borderline results need more screening or testing. Your baby’s health care provider may collect another blood sample from your baby and repeat the original screening.

Sometimes, the health care provider may do other testing, like drawing blood for laboratory tests, instead of repeating the blood spot screening. It is important to follow your health care provider’s directions about when and what kind of repeat screening or other testing your baby needs.

Health care providers might also refer to borderline results as “inconclusive” or “medium risk.”

Pulse oximetry screening determines if your child has certain forms of critical congenital heart disease (CCHD).

Most parents receive their newborn’s pulse oximetry screening results as soon as the screening is complete. Two types of results are possible:

• Pass
• Fail (also called nonpassing)

Read further to learn about each type of result.

Pass Results

A pass result means that your baby had in-range blood oxygen levels at the time of screening. Babies with pass results do not need more testing.

However, pulse oximetry screening only detects certain types of heart problems. It does not find all heart problems. Babies who develop any health problems, especially trouble breathing, changes in energy level, or trouble eating, need more testing—even if their pulse oximetry screening results were in-range.

Fail Results

A fail result means that your baby had low oxygen levels at the time of screening. Babies with fail results need more testing to determine why their oxygen levels are low.

Not every baby with a fail result has CCHD. A baby can have low oxygen levels for other reasons, like general breathing problems, infections, or minor heart problems.

To determine if your baby’s low oxygen is due to CCHD, your baby’s health care provider will usually check your baby very carefully and order diagnostic test(s). These test(s) might include an echocardiogram, electrocardiogram, and/or chest X-ray to diagnose CCHD.

Babies with fail results need this extra testing before they go home. If the birth facility cannot perform this testing, your baby should be tested at another facility right away.

Health care providers might also refer to fail results as “nonpassing.”

Most parents receive their newborn’s hearing screening results as soon as the screening is complete. Two types of results are possible:

• Pass
• Fail (also called nonpassing or refer)

Pass Results

A pass result means that your baby has typical hearing in both ears at the time of screening.

Most babies with pass results do not need more testing. However, babies who pass newborn hearing screening may still develop hearing loss later in infancy or childhood.

This is more common in babies with certain risk factors, like low birth weight or specific infections. Babies with these risk factors may need extra hearing checks—even if they pass newborn hearing screening. Learn more about risk factors for hearing loss.

Parents should be alert for any signs of hearing problems in their babies and pay attention to infant language development milestones. Language development milestones for babies who can hear include things like:

• Crying to loud sounds
• Quieting to familiar voices
• Cooing or making different voice sounds
• Looking toward voices and sounds

Watching for these milestones can help you detect any issues with your baby’s hearing.

Fail Results

A fail result in one or both ears means that your baby might be deaf or hard of hearing. Babies with fail results need more testing. These babies typically have another hearing screen within two weeks after discharge. Your baby’s health care provider can help you schedule this repeat screen before you leave the birth facility.

Babies with fail results on their repeat hearing screen should see an audiologist, a specialist in hearing problems, as soon as possible. Your baby’s health care provider or the state newborn hearing screening program may help you make arrangements for follow-up testing.

Health care providers might also call fail results “nonpassing” or “refer.”

Many parents have questions about NBS. Following is a list of questions you may want to ask after you receive your baby’s NBS results:

• Where can I get a copy of my baby’s screening results?
• What options do I have for what happens to my baby’s blood sample after screening?
• Does an in-range result mean my baby is healthy?
• Does an out-of-range result mean my baby definitely has a condition?
• Does my baby need any more testing?
• Is additional testing covered by insurance?
• What signs should I watch for in my baby?
• Whom can I contact if I have more questions?

If your baby did not pass one of the newborn screens, you should work with your baby’s health care provider to see a specialist for the follow-up testing. Your baby’s health care provider or the state NBS program will help you find the right specialist and schedule an appointment for more testing.

It is important for your baby to see a specialist whenever your health care provider recommends. Doing so is the only way to find out for sure if there is a problem with your baby’s health.

The specialist will help you learn more about your baby’s health and get access to treatment or intervention if needed. This will help make sure that your baby lives as healthy a life as possible.

Specialists your baby might see include health care providers with extra training and knowledge in the following areas:

• Genetics (medical geneticist or genetic counselor)
• Hormones (endocrinologist)
• Heart (cardiologist)
• Breathing (pulmonologist)
• Blood (hematologist)
• Immune system (immunologist)
• Nervous system (neurologist)
• Hearing (audiologist)

A

Acidic, Acids

Like an acid. In chemistry, acids are molecules that have a pH below 7. Acids can donate hydrogen ions to other molecules in chemical reactions.

Acidemia

Acid in the blood. Acidemia is caused when processes in the body are not working as they should, causing acids to build up in the blood and tissues. Acids in the blood can cause damage to the body if the condition causing acidemia is not treated.

Aciduria

Acid in the urine. Aciduria is caused when processes in the body are not working as they should, causing acids to build up in the body and come out in the urine. Acids can damage the body if the condition causing aciduria is not treated.

Acute

Severe or intense. An acute type of a condition usually has more symptoms or more intense symptoms than other forms of that condition. An acute symptom may come on quickly or need urgent care.

Acute fatty liver of pregnancy (AFLP)

A rare but serious condition in the mother that can occur late in pregnancy. Fat builds up in the mother’s liver and damages it. The most common sign of AFLP is yellow skin and/or eyes (jaundice). Sometimes, a mother’s AFLP is caused because their unborn baby has a condition that releases toxins inside the mother. If your baby’s mother had AFLP, your baby should be screened for certain newborn conditions.

Acylcarnitines

A substance that helps your body break down fats for energy. Acylcarnitines help move fat into the mitochondria (a structure inside the cell) to be broken down. In Blood Spot Screening, finding too high or too low levels of certain acylcarnitines in your baby’s blood may mean they need further testing.

Adrenal crisis

A life-threatening condition that happens when there is not enough cortisol in your body. Signs can include altered mental status, abdominal pain, nausea/vomiting, or fever. Adrenal crisis can lead to low blood pressure, seizures, and coma, and should be treated as soon as possible.

Adrenal glands

Small structures on top of your kidneys. Adrenal glands make several important chemical messengers (hormones).

Advisory Committee on Heritable Disorders in Newborns and Children (ACHDNC)

A federal committee made up of doctors, scientists, parents, ethicists, and researchers. This group advises the United States Secretary of Health and Human Services about newborn screening and related topics. Learn more about the ACHDNC.

Advocacy

Support of a cause. Advocacy organizations for newborn screening and for the conditions found by newborn screening help raise awareness, develop governmental policies, and fundraise for their cause.

Airway clearance therapy (ACT)

A physical process to help clear the lungs, such as clapping the back, chest, and sides with a cupped hand or a special tool called a percussor. Older children can also use specific methods of controlled breathing, huffing, and/or coughing. Devices like vests or inhaling tools can also be used. Also called airway clearance technique.

Aldosterone

A chemical messenger (hormone) that maintains normal salt levels in the body.

Allele

Everyone has two sets of genes – one copy inherited from your biological mom and one copy inherited from your biological dad. When these genes have slight differences, they are called alleles. These differences usually do not impact your health, but certain alleles can cause genetic conditions.

Alopecia

Hair loss, or not growing hair in places where hair normally grows.

Amino acid

A class of chemicals that have a similar structure. Proteins are chains made up of amino acids. Cells use 20 amino acids to build proteins. Examples of amino acids used to build proteins are arginine, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, tyrosine, tryptophan, and valine.

Some amino acids, like citrulline and homocysteine, are not part of proteins but have other important jobs in the body.

Amino acid disorder

Condition caused when the body has trouble breaking down certain parts of proteins called amino acids. Several genes make special proteins (called enzymes) that help break down amino acids and get rid of waste. When one of these genes does not make a working enzyme, it can cause an amino acid disorder.

Ammonia

A waste product made by your body from protein digestion. Normally, your body changes ammonia into a less toxic waste product called urea through a process called the urea cycle. Urea is passed through the body in urine. High levels of ammonia (hyperammonemia) in the body are harmful.

Analgesics

Medicines to treat pain. Examples of common analgesics include acetaminophen and ibuprofen.

Anemia

Low level of red blood cells in the blood.

Antibiotics

Medicines that kill bacteria.

Antibody

Proteins that mark foreign substances for destruction by your immune system. Antibodies attach to bad bacteria, viruses, or other substances in your body that may harm you, then immune cells kill anything the antibody is attached to. Also called immunoglobulins (Ig).

Anticoagulant

Medicine that helps prevent blood clots.

Anti-inflammatories

Medicines that reduce swelling. Common anti-inflammatories are steroids (like cortisone or prednisone) and NSAIDs (nonsteroidal anti-inflammatory drugs, like ibuprofen or naproxen).

Antimicrobial

Treatment that kills small organisms that infect the body. Antimicrobial therapies include antibiotics (kill bacteria), antivirals (kill viruses), and antifungals (kill fungi like yeast).

Antioxidant

Substance that protects the body from certain kinds of damage, like the damage caused from reactive oxygen species.

Antiviral

Treatment that kills viruses.

Apgar score

A scoring system for assessing a newborn’s health right after birth. The Apgar score measures five key areas of health: skin color, heart rate, reflexes, muscle tone, and breathing rate. Most healthy babies score 7 or higher. Babies with scores lower than 7 may need medical help. Babies with scores lower than 5 may need special hospital care.

Arginine

An amino acid that your body uses to build proteins.

Argininosuccinic acid

An amino acid that is not used to build proteins. Argininosuccinic acid is needed to build arginine, which is an amino acid used in proteins. Argininosuccinic acid is part of the urea cycle.

Arrhythmia

Irregular heartbeat. Arrhythmias include a fast heart beat (tachycardia), a slow heart beat (bradycardia), or an irregular pattern such as skipping beats.

Ataxia

A loss of balance caused by brain, nerve, or muscle damage.

Atresia

When an opening in the body is not formed correctly.

Atrophy

When parts of the body start to break down, weaken, or get smaller.

Attenuated

Weakened, reduced, or less severe.

Audiologist

A doctor who has extra training and knowledge in hearing differences and balance issues.

Audiology evaluation

A series of hearing tests an audiologist performs to see if your baby is deaf or hard of hearing and if so, to what degree.

Autoimmune

When your immune system mistakenly attacks your healthy cells.

Automated auditory brainstem response (AABR)

A type of hearing screening method used to test an infant’s ability to hear.

Autosomal dominant

One way a condition can run in families (inheritance pattern). Everyone receives two copies of all genes – one copy inherited from the mom and one copy inherited from the dad. If a condition is autosomal dominant, it means your baby can have the condition if only one of those gene copies does not work. In this case, the mom or the dad usually has the condition also.

Autosomal recessive

One way a condition can run in families (inheritance pattern). Everyone receives two copies of all genes – one copy inherited from the mom and one copy inherited from the dad. If a condition is autosomal recessive, it means your baby can have the condition if both of those gene copies do not work. In this case, the mom and the dad usually do not have the condition because only one of each of their gene copies does not work (they are carriers).

B

B cells

A type of blood cell that is a part of the immune system. B cells are made in our bone marrow and make antibodies.

Betaine

A chemical that occurs naturally in your body and in food. Betaine is used as a treatment for certain conditions with high homocysteine levels. It helps the enzyme that breaks down homocysteine work. Also called betaine anhydrous or trimethylglycine.

BH4 (tetrahydrobiopterin)

A type of biopterin that is naturally present in your body to help certain enzymes work (cofactor). It is also taken as a supplement to treat some conditions found by newborn screening.

Bilateral

Both sides. For example, bilateral hearing loss occurs in both ears.

Bilirubin

A yellowish substance made during your body's normal process of breaking down red blood cells. A healthy liver will remove most of the bilirubin in your body. If your liver is damaged or is not working well, bilirubin levels can get too high (hyperbilirubinemia). When too much bilirubin gets into the blood, it can cause your skin and eyes to turn yellow (jaundice).

Biopterin

A group of substances that help certain enzymes work (cofactors). Tetrahydrobiopterin (BH4) is a type of biopterin.

Biosynthesis

Processes inside your body that build complex substances from simple ones.

Biotin

A vitamin that is needed to help your body break down food and make energy. It is an enzyme cofactor (it helps processes in the body happen). Biotin is so important that your body recycles it so there is always some available.

Birth prevalence

A measure of how often a condition is found in newborns. If the birth prevalence is 1 in 1000, that means that in a group of 1000 newborns, one newborn has the condition.

Bone marrow

The space inside your bones where blood cells are made.

Branched-chain amino acids

A type of amino acid (the building blocks of proteins) with a chemical structure that looks like a branch. The branched amino acids are leucine, isoleucine, and valine.

Bronchodilators

Medicines that widen the airways of the lungs.

C

Candidiasis

An infection of the body with yeast (a type of fungus). It is commonly called thrush when it happens in the mouth. When it happens in the vagina, it is commonly called a yeast infection. Some diaper rashes are caused by candidiasis on the skin.

Cardiologist

A doctor with extra training in the heart and blood vessels.

Cardiomyopathy

A large, thick, or stiff heart that has trouble pumping blood to the body.

Carnitine

A substance that helps your body break down fats for energy. Pieces of fats are attached to carnitine to form an acylcarnitine. Acylcarnitine helps move the fat into the mitochondria (a structure inside the cell) to be broken down.

In Blood Spot Screening, finding high or low levels of carnitine in your baby’s blood may mean they need further testing.

L-carnitine is a common treatment given to babies with certain conditions to help them digest fats.

Carrier

Everyone has two sets of genes – one copy inherited from your mom and one copy inherited from your dad. Some conditions only occur when both copies of a certain gene do not work (autosomal recessive). For these conditions, people who have one normal gene copy and one gene copy that does not work are called carriers. Carriers do not have the condition, but they can pass it on to their baby. If a carrier has a child with another a carrier, their child has a 1 in 4 chance of getting two gene copies that do not work.

Cataracts

Cloudy spots on the eye.

Channel

A type of protein that allows atoms, like chloride, to go in and out of cells.

Chaperone therapy

Medicine that improves enzyme activity.

Chromosome

Thread-like DNA structures that contain all of your genetic material. You have 46 chromosomes that are in 23 pairs. 22 of the pairs look the same for men and women. The 23rd chromosome pair is called the sex chromosome pair. Typical biological females have two X chromosomes (XX). Typical biological males have one X chromosome and one Y chromosome (XY).

Chronic

Ongoing. A chronic condition can either last a long time or can constantly come and go.

Chloride

An atom that your body uses to control acidity and fluid levels in cells.

Cholestasis

A liver disease. Bile is a fluid that your liver makes to help you digest food. In cholestasis, bile is blocked or reduced. Signs of cholestasis in babies include yellow skin or eyes, dark urine, and light-colored stool.

Citrulline

An amino acid that is not used to build proteins. Citrulline is needed to build arginine, which is an amino acid used in proteins. Citrulline is part of the urea cycle.

Classic phenylketonuria

Classic phenylketonuria (PKU) screening test is a blood test given to newborns one to three days after birth. PKU stands for phenylketonuria

Cleft palate

A hole in the top of the mouth (palate) that can sometimes include an opening in the lip (cleft lip). Cleft palate occurs when the top of the mouth does not come together before birth.

Critical congenital heart disease (CCHD)

A group of serious heart conditions present at birth. Children with these conditions usually need surgery or other intervention before 1 year of age.

Cochlear implants

A device that converts sound into electrical signals and then transfers those signals directly to a nerve that helps the person hear. Cochlear implants are put in during outpatient surgery.

Cofactor

Substances that help enzymes work. Examples of cofactors are biotin, vitamin B-12, and tetrahydrobiopterin (BH4).

Coma

A deep state of prolonged unconsciousness from which a person cannot be awakened.

Community-based organizations (CBOs)

In medical terms, local agencies that provide services, education, and support to families affected by certain conditions.

Congenital

Present at or before birth. Congenital infections happen when the baby is infected with a virus before or during birth.

Contracture

Tightening that can prevent normal movement of a body part.

Cortisol

A chemical messenger (hormone) that keeps blood sugar levels normal and protects the body during stress.

Creatine synthesis disorder

Condition caused when the body has trouble making creatine. Certain genes make proteins (enzymes) that are needed to make creatine. When one of those genes does not work, it can cause a creatine synthesis disorder. Also called creatine deficiency syndrome.

Cued speech

A visual method of speech that uses hand signals to communicate speech sounds. Cued speech is different from American Sign Language, which uses hand signals to communicate words or concepts.

Cyanosis

Blue color to the skin, lips, or fingernails that is usually caused by low oxygen levels.

Cysts

Fluid-filled sacs in or on the body.

D

Defect

Something in the body has not formed in the typical way.

Deficiency

Lacking, not enough, or low levels.

Dehydration

Not enough fluid in the body. In babies, signs of dehydration include fewer than 6 wet diapers in a day, dry mouth, fewer tears when crying, sunken eyes, greyish skin, or a sunken soft spot.

Developmental delay

Not growing or learning new skills as quickly as expected, not reaching milestones or not progressing to new ones.

Diagnose

When a health care provider determines which medical condition your baby has.

Diagnostic test

A test used to confirm or rule out the presence of a medical condition.

Dialysis

A treatment that filters blood.

E

Echocardiogram

An ultrasound picture of the heart. An ultrasound creates an image of the inside of your body using sound waves.

Ectopia lentis

When the lens in the eye is in the wrong place.

Eczema

Dry, scaly skin.

Electrocardiogram (ECG)

A test that records the electrical activity of the heart.

Endocrine disorder

A condition that produces too much or too little chemical messengers (hormones) in the body.

Endocrinologist

A doctor with extra training in how hormones (chemical messengers) and glands (body structures that make hormones) work in the body.

Enzyme

Proteins that make or speed up chemical changes. Enzymes can build, break down, or change substances in the body. There are over a thousand enzymes inside your cells that help your body with the processes needed for life.

Enzyme replacement therapy

A treatment where an enzyme that the body needs is provided into the blood (intravenously). In conditions where an enzyme is not made correctly by your body, replacing it with a working enzyme can relieve symptoms.

Epilepsy

A condition in the brain that causes sudden changes in the brain’s electricity (seizures).

F

Failure to thrive

When a baby is not growing enough compared to average babies. Failure to thrive can occur when babies have a condition that does not let them use food for energy as well as they need to.

False-negative result

A result that is in-range, even though the newborn has the condition.

False-positive result

A result that is out-of-range, even though the newborn does not have the condition.

Fasting

Going a long time without food. Babies with certain conditions must eat frequently (avoid fasting) to prevent symptoms.

Fatty acid

A type of fat. Fatty acids can be saturated or unsaturated, and can also be very long chain, long chain, medium chain, or small chain depending on their chemical structure.

Fatty acid oxidation disorder

Condition caused when the body has trouble breaking down fats and turning them into energy. Several genes make proteins (enzymes and transporters) that help break down fats. When one of these genes does not work, a fatty acid oxidation disorder can result.

Fibrosis

When the body creates scar tissue. In conditions with fibrosis, too much scar tissue may be created where it does not belong.

Fluctuating

Changing. Babies with fluctuating hearing loss may get better or worse over time.

Folate

One of the B vitamins, also called folic acid or vitamin B9.

G

Galactose

A type of sugar that is found in food, including milk and products made from milk. Your body also makes galactose when it breaks apart another sugar found in milk called lactose.

Gene

A message written in the DNA inside every cell that gives the body instructions on how to build a certain protein. Each of our cells has two copies of most genes, one copy from our biological mother and one copy from our biological father. We have thousands of different genes.

Gene therapy

Gene therapy treats genetic conditions caused when certain genes in the body do not work correctly. Gene therapy delivers working copies of the gene to cells in the body. The cells use the working gene copies to make important proteins needed for the body to function. The ability of the body to make these proteins with the new working gene copies helps treat the signs and symptoms of the genetic condition. Gene therapy is available for a few different genetic conditions.

Genetic

Having to do with genes. For example, a genetic condition is caused by a nonworking gene.

Genetic condition

A condition caused by an error in a gene. Errors in genes can be passed down from parent to child (inherited). Errors can also happen in a baby’s genes even when the parents do not have an error in their genes (sporadic).

Genetic counselor

A counselor who has extra training and knowledge in changes to our genes that can affect our health. They also provide support to those with genetic conditions.

Glycine

An amino acid that your body uses to build proteins.

Glycogen

A substance made when your body links many sugars together. Glycogen is how your body stores sugar for later use.

Glycosaminoglycans (GAGs)

Complex sugars that your body breaks down in the lysosomes (special compartments inside your cells that process nutrients).

Glycosphingolipid

A type of fat that is necessary for healthy cells but can be harmful at high levels.

H

Health care provider

Any person, such as a primary care physician, nurse, or therapist, who provides health care services for you or your baby.

Hematologist

A doctor with extra training on conditions involving the blood or parts of the body that make blood, like the bone marrow and spleen. Hematologists also treat conditions involving the lymphatic system, a system that helps remove waste from the blood.

Hemoglobin (Hgb)

A protein that is responsible for carrying oxygen and carbon dioxide in the blood inside red blood cells. Hemoglobin also contains iron that is responsible for the red color of blood. There are many types of hemoglobin. Fetal hemoglobin, or hemoglobin F, is found in all babies. Hemoglobin S (sickle hemoglobin) and hemoglobin C can cause conditions (called hemoglobinopathies) that affect the blood.

Hemoglobin disorder or hemoglobinopathy

A condition caused by changes to hemoglobin that affect the shape or amount of red blood cells in the body in an unhealthy way.

Hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome

A rare but serious condition in the mother during pregnancy that includes a breakdown of red blood cells (hemolysis), liver damage (elevated liver enzymes), and low clotting cells (platelets) in your blood. This condition may result when the baby has certain health conditions. Babies of mothers who had this condition should be screened for certain newborn conditions.

Hemolytic anemia

A condition caused when red blood cells are destroyed too quickly.

Hepatomegaly

Unusually large liver.

Hernia

Part of the intestine or fatty tissue forms a soft bump under the skin at a weak spot in the body. An umbilical hernia happens near the belly button. An inguinal hernia happens near the groin.

Heterozygote

A person with one working copy and one nonworking copy of a gene. Sometimes called a carrier.

Histidine

An amino acid that your body uses to build proteins.

Homocysteine

An amino acid that is not used to build proteins. Homocysteine is needed to make the amino acid methionine, which is used to make proteins. Homocysteine is also formed when methionine is broken down. Homocystinuria is a condition that occurs when homocysteine builds up.

Hormones

Chemical messengers in the body. Examples of hormones include aldosterone and cortisol.

Hydroxylysine

An amino acid that your body makes from lysine. Hydroxylysine is found in collagen, a protein present in our skin and bones.

Hydroxyurea

A medicine that can make red blood cells stay round and more flexible. It is used to treat some hemoglobin disorders.

Hyperalimentation

A nutritional formula that is given into the blood for someone who cannot receive food or fluids by mouth.

Hyperammonemia

High levels of ammonia in the blood. Hyperammonemia is a dangerous condition that can happen if ammonia is not removed from the body in urine.

Signs of hyperammonemia in babies include poor feeding, sleepiness, vomiting, seizures, and low body temperature.

Hyperbilirubinemia

High levels of bilirubin in the blood. Hyperbilirubinemia occurs when the liver cannot get rid of bilirubin. High bilirubin turns the skin and eyes yellow (jaundice).

Hyperplasia

When a part of the body keeps growing and becomes too large.

Hypoglycemia

Low blood sugar. Our bodies need blood sugar for energy, especially in our brain. When a condition prevents the body from breaking down food for energy, blood sugar can drop to dangerously low levels.

Signs of hypoglycemia in babies include poor feeding, shaking, pale or blue skin or lips, low energy, seizures, floppy arms and legs, low body temperature, and stopping breathing.

Hypotonia

Floppy arms and legs, weak muscle tone.

I

Immunoglobulin replacement therapy

A treatment that adds antibodies (also called immunoglobulins) to your blood (intravenously) to help you fight infections. Sometimes called IVIG for intravenous immunoglobin.

Immunologist

A doctor with extra training in the immune system, the part of the body that fights infections.

In-range result

A result that is inside the range of expected results for typical babies. An in-range result means your baby likely does not have the condition that the screen is checking for.

Inherit

In medical terms, passing down genes from parents to children. Genes determine how your body develops, including your hair color, eye color, and whether you have certain genetic conditions.

Injection

When medicine is delivered into your body by a needle, often called a “shot.”

Insulin

A protein in the body that helps the body use sugar for energy and controls blood sugar levels. Higher insulin levels lead to lower blood sugar levels.

Intermittent

Comes and goes.

Intervention

An action taken to change a health outcome.

Intravenous

Delivered into your blood through a vein.

Involuntary

Movements that we do not make on purpose. For example, involuntary body movements include our heart beating. Sometimes problems in the brain can cause other movements to be involuntary, like twitches, spasms, or jerking our arms and legs.

Iodine

A mineral that is important for the thyroid gland to function.

Isoleucine

An amino acid that your body uses to build proteins.

J

Jaundice

A condition where high amounts of bilirubin in the body turn the skin and/or eyes yellow or orange. Jaundice can happen in healthy babies soon after birth, especially if they are born early. Jaundice can also mean that the baby has an infection, liver issues, or a health condition.

K

Kernicterus

A rare condition caused when high levels of bilirubin damage the brain.

Ketones

Your body makes ketones when it breaks down fat for energy. Ketones are usually made when the sugar in your blood is low (hypoglycemia).

L

Lactose

A type of sugar present in milk and some products that are made from milk, like ice cream or cheese.

Lethargy

Sleepiness or lack of energy.

Leucine

An amino acid that your body uses to build proteins.

Leukodystrophy

A rare, inherited condition that causes damage to the brain’s myelin.

Lymph nodes

Small structures (glands) in the body that filter germs like bacteria and viruses out of our system.

Lymphocytes

Special white blood cells that the immune system uses to fight against germs that invade the body. Lymphocytes include T cells, B cells, and natural killer (NK) cells.

Lysine

An amino acid that your body uses to build proteins.

Lysosomal storage disorder

Lysosomes are tiny components in cells that contain enzymes that process nutrients. Lysosomal storage disorders are conditions where certain enzymes do not work. This causes unprocessed nutrients to build up, resulting in damage to many areas of the body.

Lysosomes

Special compartments inside your cells that process many nutrients your body needs.

M

Macrocephaly

Large head size.

Macroglossia

Large tongue.

Magnetic resonance imaging (MRI)

A scan that makes detailed images of the inside of the body.

Medical geneticist

A doctor who has additional training in changes to our genes that can affect our health.

Medium chain triglyceride (MCT) oil

A medicine that contains a specific type of fat that is smaller than regular fats. It is given to babies that cannot digest fat from food easily. MCT oil provides your baby’s body with a fat that is easier to digest and turn into energy.

Metabolic crisis

A serious condition that can happen in people with a metabolic disorder. A metabolic crisis occurs when the blood sugar gets too low (hypoglycemia) and toxic substances like ammonia get too high (hyperammonemia).

Metabolic disorder

Metabolism is the complex process our bodies use to keep us alive. A metabolic disorder occurs when a change to this process makes it more difficult for the body to make energy and get rid of toxins. The RUSP has three categories of metabolic disorders: organic acid disorders, fatty acid disorders, and amino acid disorders.

Metabolism

Process of getting energy from food.

Methionine

An amino acid that your body uses to build proteins.

Microcephaly

Small head size.

Milestone

In medical terms, an action or event marking a major change or stage in development.

Milestone regression

Losing skills that were already learned and falling behind on developmental stages after already meeting them.

Mitochondria

Rod-shaped structure inside a cell. Mitochondria act like a digestive system, which takes in nutrients, breaks them down, and creates energy for the cell. Often called the powerhouse of the cell, mitochondria are in charge of releasing energy from food.

Monitor

In medical terms, when a health care provider keeps track of your baby’s overall health, symptoms, or test results.

Myelin

Protective covering of nerve cells.

Myopathic

Having weak muscles.

Myopia

Nearsighted. People with myopia can see well up close but have trouble seeing objects that are far away.

N

Natural killer (NK) cells

Immune cells (lymphocytes) in the blood that can kill infectious cells without being activated by other cells.

Nausea

Feeling of stomach discomfort or wanting to vomit.

Neuromuscular disorder

A condition that causes problems with the nerves and muscles in your body.

Neurologist

A doctor with extra training on the brain, spinal cord, and nerves.

Neurotransmitters

Chemicals that carry messages from one part of the brain to another.

Newborn intensive care unit (NICU)

A unit in the hospital that cares for babies that need special help with staying warm, feeding, and other medical needs.

Newborn screening (NBS)

The process of checking babies to identify those who might have certain serious health conditions that can benefit from early treatment or intervention.

Newborn screening panel

A list of conditions for which newborns receive screening at or shortly after birth.

O

Ophthalmologist

Eye doctor.

Organic acid disorder

Conditions caused when the body has trouble breaking down fats and proteins and turning them into energy. Several genes make proteins (enzymes) that are needed for breaking down fats and proteins. When one of these genes does not work, it can cause an organic acid disorder. Also called organic acid condition.

Other disorder

Conditions that are found by newborn screening that do not fit into the condition categories of metabolic disorder, endocrine disorder, or hemoglobin disorder as defined by the ACHDNC.

Otoacoustic emissions (OAE)

A type of hearing screening method used to test an infant’s ability to hear.

Out-of-range result

A result that is outside the range of results for typical babies. An out-of-range result means your baby might have a condition and needs further testing.

P

Pancreatic enzymes

Enzymes that the pancreas makes and puts into our intestines to help us digest food.

Peripheral

In medical terms, away from the center. For example, peripheral vision is what you see around all sides of what you are focusing on.

Peroxisomal disorder

Peroxisomes are tiny components in cells that help break down fats. Peroxisomal disorders are conditions that cause fats to build up in the cells. The buildup of fats causes damage to many areas of the body.

Peroxisomes

Tiny components in cells that help break down fats.

Phenylalanine

An amino acid that your body uses to build proteins.

Photophobia

Sensitivity to light.

Phototherapy

Treatment using light. For example, blue-green light is used to treat babies with high levels of bilirubin (jaundice). The light changes the bilirubin into a form that babies can get rid of through urine. Babies wear eye covers to protect their eyes during treatment. Health care providers check the babies’ blood to determine when the bilirubin has returned to safe levels. When used for jaundice, phototherapy is also called “bili lights.”

Pseudodeficiency

A type of false-positive that can occur during screening for certain conditions. Babies with pseudodeficiency have a change in one of their enzymes. Their enzyme works normally in the body, but the screen can only see that it is changed and cannot see that it is working. Babies with pseudodeficiency do not have the condition. Follow-up testing determines if your baby has the condition or has a pseudodeficiency.

Premature

Babies that were born early, before the 37th week of pregnancy.

Primary immune disorder

A condition that prevents the body from developing a normal immune system. Our immune system is needed to fight infections.

Profound

A severe form of a condition. For example, babies with profound hearing loss typically only experience loud sounds as vibrations.

Pulmonologist

A doctor with extra training in the lungs and airways.

Pulse oximetry

A test used to measure how much oxygen is in the blood.

Q

Quality improvement

A framework used to systematically improve care. Quality improvement seeks to standardize processes and structure to reduce variation, achieve predictable results, and improve outcomes for patients, healthcare systems, and organizations. Structure includes things like technology, culture, leadership, and physical capital; process includes knowledge capital (e.g., standard operating procedures) or human capital (e.g., education and training).

R

Reactive oxygen species

A type of unstable molecule that, at high levels, can damage cells.

Recommended Uniform Screening Panel (RUSP)

The list of conditions for which the United States Secretary of Health and Human Services recommends newborns receive screening.

Red blood cells

Round red cells in your blood that use hemoglobin to carry oxygen from the lungs to the body and carry carbon dioxide from the body to the lungs.

Regenerate

To make again. For example, the process where your body recycles cofactors to use them again.

Retinopathy

Eye problems. Retinopathy is damage to the blood vessels in the back of the eye.

S

Secretary of Health and Human Services (HHS)

The person who administers the United States Department of Health and Human Services (part of the U.S. government).

Seizure

A sudden change in the brain’s electricity. There are many types of seizures depending on what part of the brain is changing. Signs of a seizure in babies can include any one of the following: staring, rapid eye blinking, breathing problems, head nodding, jerking movements, becoming stiff, or passing out.

Sensor

A device that detects or measures something.

Septal defects

Holes in the heart. Ventricular septal defects are holes in the wall (septum) that separates the left and right lower chambers (ventricles) of the heart. Atrial septal defects are holes in the septum that separates the left and right upper chambers (atria) of the heart.

Sickle

A sickle shape is a curved shape, like a crescent moon or the letter C. When red blood cells are sickle-shaped instead of round, they break down more easily and can also get stuck in the blood vessels.

Sodium

An atom that your body uses to control fluid levels in cells. It is also needed for our muscles and nerves to work.

Spasm

Sudden muscle movements that we cannot control. They can occur in any muscle in the body, including the heart.

Spasticity

Muscle tightness or stiffness.

Specialist

A health care professional who has extra training and knowledge and whose practice is limited to a specific area of medicine.

Specimen

A sample used for testing. Examples include a dried blood spot, a tube of blood, a sample of urine, or a skin sample.

Spleen

An organ located under your ribs and above your stomach. The spleen gets rid of old or damaged red blood cells. The spleen also helps the immune system fight infection.

Sporadic

Happening sometimes with no pattern. A sporadic condition is not passed down from parent to child.

Statin

Medicine that lowers cholesterol levels.

Stem cell transplantation (SCT)

Stem cells can develop into any type of cell, such as blood cells, brain cells, heart muscle cells, or bone cells. Stem cell transplantation is the process of removing stem cells from a healthy person and injecting them into someone who needs them. Some conditions can be treated with stem cells.

Substrate reduction therapy

Medicine that prevents your body from making a substance. For example, in Gaucher disease, the body cannot break down glucocerebroside, a substance that your body uses in certain cell processes. Glucocerebroside builds up and causes damage. Substrate reduction therapy helps prevent the body from making glucocerebroside.

Succinylacetone

A substance formed when your body breaks down the amino acid tyrosine. Normally, the body breaks down succinylacetone rapidly. When a condition prevents that process, too much succinylacetone builds up and can damage the liver and kidneys.

Supplement

To add. In the case of many newborn conditions, your baby’s diet needs a supplement of an important nutrient or nutrients to help their body’s processes work better.

Syndrome

A group of symptoms that often occur together, or a condition that includes symptoms in different parts of the body.

T

T cells

Immune cells (lymphocytes) in the blood that fight dangerous germs.

T cell receptor excision circles (TRECs)

Small pieces of extra, nonfunctional DNA that are present in the blood when the body is making T cells. Low levels of TRECs in newborns can mean that the immune system is not working as it should.

Tachypnea

Rapid or troubled breathing.

Tetrahydrobiopterin (BH4)

A type of biopterin that is naturally present in your body to help certain enzymes work (cofactor). It is also taken as a supplement to treat some conditions found by newborn screening.

Thiamine

Also called vitamin B-1, this vitamin is needed for certain enzymes to work (a cofactor).

Thrush

Patchy white dots in the mouth or throat that do not get better. Also called candidiasis. Thrush is an infection caused by yeast (a type of fungus).

Thymus

A small structure (gland) in your chest that functions until puberty. The thymus gland helps develop the immune system.

Thyroid gland

A butterfly-shaped organ in the neck. It makes hormones that help in growth and development. It is also important for many body processes that help you live, such as metabolism.

Total parenteral nutrition (TPN)

A nutritional formula that is given into the blood for someone who cannot receive food or fluids by mouth.

Trait

A feature that is a part of you, like the color of your eyes or how tall you are.

In hemoglobin disorders, a hemoglobin trait or sickle cell trait refers to having one hemoglobin gene that does not work. Everyone has two copies of each gene – one inherited from the mom and one inherited from the dad. People with a hemoglobin disorder have two nonworking hemoglobin genes. People with a hemoglobin trait have one normal hemoglobin gene and one gene that does not work. People with a hemoglobin trait usually do not have symptoms of a hemoglobin disorder.

Trait may also refer to sexual traits. Sexual traits are differences in your body that are a result of your biological sex (male or female). Chest hair is an example of a sexual trait because it is more often seen in biological males.

Transfusion

A medical procedure in which you receive healthy blood directly through a blood vessel (intravenous).

Transient

Temporary, not permanent.

Transplant

When a part of your body is replaced with a part from somewhere else, like a donation from another person. Examples of transplants related to newborn screening are liver, stem cell, bone marrow, or thymus transplants.

Transporter

A protein that helps substances move from one part of the cell to another.

Tryptophan

An amino acid that your body uses to build proteins.

Tyrosine

An amino acid that your body uses to build proteins.

U

Unilateral

One side. For example, unilateral hearing loss occurs in one ear.

Uptake scan

A procedure that makes an image of the thyroid gland and also tests its function. The uptake test measures how much radioactive iodine the thyroid takes in. The scan checks the size, shape, and location of the thyroid.

Urea cycle

A process in which waste (ammonia) is turned into a less toxic form (urea). When you eat proteins, the body breaks them down into amino acids. Amino acids are broken down further into ammonia. Ammonia is toxic, so the urea cycle changes it to urea, which is removed from the body in your urine.

Urea cycle disorder

Condition caused when the urea cycle is not working. Several genes make proteins (enzymes) that are required for the urea cycle to remove ammonia (a waste product) from the body. When one of these genes does not make a working enzyme, it can cause a urea cycle disorder.

V

Valine

An amino acid that your body uses to build proteins.

Variant

A different version. Hemoglobin variants are different versions of hemoglobin. Conditions may have variants that show different symptoms.

Gene variants are different versions of the same gene (previously called gene mutations).

Virilizing

The development of male sex characteristics (traits) like facial hair, typically because of too much of certain male sex hormones.

Voluntary

Movements that we mean to make, like when we want to pick something up and our hand closes around the object.

Vomiting

When the digestive system pushes food out of the mouth, also called “throwing up.”

W

White blood cells

Cells in your blood that are part of the immune system. Lymphocytes, B cells, T cells, and natural killer (NK) cells are all white blood cells.

X

X-linked recessive

One way a condition can run in families (inheritance pattern). Everyone has two copies of each gene – one inherited from the mom and one inherited from the dad. If a condition is X-linked, it means the gene lives on the X chromosome. If a condition is X-linked recessive, it means your baby can only have the condition if they do not have a working copy of the gene.

Biological girls have two X chromosomes and biological boys only have one X chromosome. This means girls who have one nonworking gene on the X chromosome can have a working copy of the gene on their second X chromosome. Boys who have a nonworking gene do not have a second (backup) working gene. X-linked conditions are often more frequent and more severe in boys because they do not have a backup X chromosome.