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Newborn Screening Tests


Deborah M. Consolini

, MD, Thomas Jefferson University Hospital

Reviewed/Revised Sep 2023

Screening tests are done to detect health conditions that are not yet causing symptoms. Many serious disorders that are not apparent at birth can be detected by various screening tests. Early diagnosis and prompt treatment can reduce or prevent many disorders that may interfere with an infant's healthy development. In the United States, some tests are done routinely and some are required by the state. When screening tests are positive, further testing is often done.

Typical screening tests include

  • Blood tests

  • Tests of oxygen level

  • Hearing tests

All newborns are evaluated for jaundice Jaundice in the Newborn Jaundice is a yellow color to the skin and/or eyes caused by an increase in bilirubin in the bloodstream. Bilirubin is a yellow substance formed when hemoglobin (the part of red blood cells... read more Jaundice in the Newborn (a yellow color of the skin caused by elevated levels of bilirubin in the blood) by looking at the skin and whites of the eyes, using a skin sensor, doing a blood test, or a combination.

Many government organizations require a number of blood tests in newborns to detect certain inherited metabolic disorders Overview of Hereditary Metabolic Disorders Hereditary metabolic disorders are inherited genetic conditions that cause metabolism problems. Heredity is the passing of genes from one generation to the next. Children inherit their parents'... read more that are treatable. Common tests include those for phenylketonuria Phenylketonuria (PKU) Phenylketonuria is a disorder of amino acid metabolism that occurs in infants born without the ability to normally break down an amino acid called phenylalanine. Phenylalanine, which is toxic... read more , maple syrup urine disease Maple syrup urine disease Amino acid metabolism disorders are hereditary metabolic disorders. Hereditary disorders occur when parents pass the defective genes that cause these disorders on to their children. In most... read more , galactosemia Galactosemia Galactosemia (a high blood level of galactose) is a carbohydrate metabolism disorder that is caused by a lack of one of the enzymes necessary for metabolizing galactose, a sugar that is part... read more , congenital adrenal hyperplasia, sickle cell disease Sickle Cell Disease Sickle cell disease is an inherited genetic abnormality of hemoglobin (the oxygen-carrying protein found in red blood cells) characterized by sickle (crescent)-shaped red blood cells and chronic... read more Sickle Cell Disease , and hypothyroidism Hypothyroidism in Infants and Children Hypothyroidism is decreased production of thyroid hormone. Hypothyroidism in children usually occurs when there is a structural problem with the thyroid gland or the thyroid gland is inflamed... read more . Some organizations also require testing for cystic fibrosis Cystic Fibrosis (CF) Cystic fibrosis is a hereditary disease that causes certain glands to produce abnormally thick secretions, resulting in tissue and organ damage, especially in the lungs and the digestive tract... read more and severe combined immunodeficiency Severe Combined Immunodeficiency (SCID) Severe combined immunodeficiency is a primary immunodeficiency disorder resulting in low levels of antibodies (immunoglobulins) and low or no T cells (lymphocytes). Most infants with severe... read more . However, in the United States, different states require different tests. For a list of routine newborn screening tests by state, see Conditions Screened By State.

Doctors place an oxygen sensor (pulse oximetry) on the newborn's right hand and right foot to measure oxygen levels. Low oxygen levels or significant differences between the hand and foot suggest the possibility of congenital heart disease Overview of Heart Defects About one in 100 babies is born with a heart defect. Some are severe, but many are not. Defects may involve abnormal formation of the heart's walls or valves or of the blood vessels that enter... read more .

Hearing tests are done to detect hearing loss Hearing Impairment in Children Hearing impairment refers to any degree of hearing loss, mild to severe, and can occur when there is a problem with a part of the ear, including the inner, middle, and outer ears, or the nerves... read more Hearing Impairment in Children , which may accompany certain birth defects or infections. Doctors use a handheld device that produces soft clicks and measures the echoes off the newborn's eardrum (called evoked otoacoustic emissions testing Testing Testing ).

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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