What is newborn screening?


Newborn screening is a public health program that is designed to identify babies with treatable medical conditions to prevent or lessen health problems. Babies with these conditions often look healthy, but still have a serious disease. Early diagnosis through newborn screening allows treatment to be started as soon as possible, hopefully before complications develop.

Every state in the United States has a newborn screening program, including New Hampshire. Newborn screening in New Hampshire tests babies for several groups of medical disorders including metabolic conditions, endocrine conditions, hemoglobin conditions, congenital hearing loss, critical congenital heart disease and other genetic conditions that do not fall into the above groups.

Metabolic conditions are caused by problems with enzymes. Enzymes are special proteins in our body that help us process and break down food and chemicals. When the enzymes do not work, proteins that our body needs may not be made or toxic chemicals can build up. This can lead to serious medical problems including difficulties with growth, seizures, developmental delay and even in some cases death. Often with early diagnosis, metabolic conditions can be treated to avoid serious health problems. Medicine or changes in diet are often necessary for treatment.

When babies make too much or too little of certain hormones this is called an endocrine condition. Hormones are chemicals that control activities in our body. One example of an endocrine condition is congenital hypothyroidism. If a baby with congenital hypothyroidism is not treated with medication they can develop growth problems and developmental delays.

Hemoglobin is the part of the blood that carries oxygen to all parts of the body. Hemoglobin disorders, such as sickle cell anemia, are also part of newborn screening. Sickle cell anemia is an inherited blood disorder characterized by chronic anemia and episodes of pain. Many treatments are available for hemoglobin disorders to help symptoms and prevent complications.

Critical congenital heart disease is another condition screened for in New Hampshire. Sometimes a baby’s heart does not form normally which can affect how the heart is able to pump blood. Heart problems may not be found before a baby is born and sometimes they do not become a problem until after the baby is already home from the hospital. Critical congenital heart disease can be life threatening if is not treated so it is recommended that all babies are screened shortly after birth.

It is also recommended that newborn babies are screened for congenital hearing loss. There are many reasons that a baby may be born with hearing loss. Sometimes things happen during the pregnancy that affect a baby’s hearing and sometimes babies may have a birth defect that causes the ear to not form normally. Most commonly the hearing loss is caused by a genetic condition. Regardless of the cause without early identification and treatment, congenital hearing loss can cause delays in speech development.

Lastly there are other genetic disorders that are part of the newborn screening program that do not fit into the groups mentioned above. One example is cystic fibrosis, which is a disorder that affects the lungs and digestive system. Babies with this condition have problems gaining weight and chronic lung infections. Another example is a condition called severe combined immune deficiency or SCID. SCID is a condition that causes problems with a baby’s immune system. Both of these conditions can be life threatening without medical treatment.

Almost all of the newborn screening tests, except for the screening for congenital hearing loss and critical congenital heart disease, are performed with a blood test. A few drops of blood from the baby’s heel are placed onto a special filter paper. This is usually done when the baby is 24-48 hours old before they leave the hospital. The blood is then sent to the laboratory for testing.

The results from the newborn screening tests will be sent to your baby’s doctor. If your baby has a positive newborn screening test you will be contacted by your baby’s doctor or someone from the state newborn screening program and they will explain what you will need to do next. Newborn screening is not perfect, so not every child with a positive screening test will have the condition. Usually further screening and testing is needed after a positive screen to make a diagnosis.

It is important to remember that most of the conditions that are tested for as part of the newborn screening program are very rare. Most babies identified by newborn screening with one of these conditions do not have any other affected family members. Many of the conditions are carried by parents with no symptoms. Newborn screening is performed on every baby so that babies who need treatment are found as soon as possible. Even though most babies are born without any of the conditions tested, if your baby has one of these rare conditions, newborn screening could save your baby’s life.

Jillian Ozmore, MS, LGC is a Licensed Genetic Counselor for the Children’s Hospital at Dartmouth-Hitchcock. She has particular interest in newborn screening and has served on the New Hampshire Newborn Screening Advisory Committee since 2007. Ozmore offers services for both pediatric and adult patients at Dartmouth-Hitchcock Manchester, Dartmouth-Hitchcock Nashua and Dartmouth-Hitchcock Medical Center. For more information visit CHaDkids.org/genetics.  

Categories: Planning for baby