Newborn Screening Laboratory

The New Jersey Department of Health’s Newborn Screening Laboratory tests more than 110,000 dried blood spot samples each year from newborns in New Jersey. State law requires that every baby born in the state of New Jersey be screened for 60 disorders that can cause serious and life-threatening problems, if undetected and left untreated. These disorders may not be apparent at birth, but if left untreated, can lead to problems that include intellectual or physical disability, or even death.

Newborn screening begins with the collection of the blood specimen from an infant. Twenty four to forty eight hours after a baby is born, a few drops of blood are taken from the baby’s heel during a relatively simple and quick procedure called a heel stick. During this procedure, the infant’s heel is pricked to draw a few drops of blood. The drops of blood are then collected on a special filter paper collection kit, obtained from the state department of health. These blood spots are allowed to dry. Then, the specimen is sent to the state department of health’s newborn screening laboratory where it is tested for a panel of disorders to identify if any abnormalities are present. If so, further confirmatory testing is done and families are connected with providers that offer treatment, optimally before onset of symptoms.

Babies with abnormal screening results are closely followed by New Jersey’s Newborn Screening and Genetic Services Program in Special Child Health and Early Intervention Services to ensure that affected newborns and their families are referred to the appropriate specialty care centers to receive timely and appropriate services.

The purpose of newborn screening is to identify infants at risk for disorders which, if left untreated, may result in developmental delays, physical and mental disabilities, and/or death.

As with any screening test, both false positive and false negative results can occur. The results of screening tests do not establish a diagnosis, but rather serve to identify a subset of patients who warrant further testing. The newborn screening laboratory screens for the classical forms of disorders; all "variant" forms may not be detected. It is critical that practitioners be aware that newborn screening may not reveal all affected infants and does not replace a physician’s clinical awareness and diagnostic capability for the disorders screened and not screened.

In 1961, newborn screening began when Dr. Robert Guthrie developed a simple test for phenylketonuria (PKU), a rare autosomal recessive disease. A drop of blood collected by pricking a newborn’s heel (a relatively risk-free procedure) is absorbed by a piece of special filter paper and the level of phenylalanine, an amino acid, in the infant’s blood is measured by analysis of the sample of dried blood. Today, a variety of disorders can be screened for by testing a single specimen containing only 5 drops of a baby’s blood.


Last Reviewed: 12/8/2023