Screening tests are special diagnostic examinations taken at birth to check if a newborn has certain potentially harmful diseases. In compliance with U.S. state law, doctors take a blood sample from the heel, which is analyzed for any number of diseases and birth defects. The sample is usually taken on the day after birth, and usually involves only two or three drops of blood. A separate test is also performed to check that the baby’s hearing is properly functioning.
The motivation for checking at birth is strictly logical: by examining a child at birth, doctors are able to catch and treat or prepare a strategy for treating any indicated problems. If this strikes parents with some alarm, the results aren’t necessarily dire news: most screenings only show indicators that doctors should pursue more tests before making a final diagnosis.
Most newborns pass the screening tests with flying colors: statistics show less than one tenth of one percent are ever found to have the tests’ targets, despite often comprehensive blood workups. However, because each state separately determines which tests are given, different states routinely provide different combinations and batches of tests.
Common Types of Tests
Blood tests are usually taken to check for treatable genetic, endocrinologic (hormonal), metabolic, or hematologic (blood-related) diseases. The tests are not mandated arbitrarily. Common factors for determining whether to include the test include:
– whether the disease can be diagnosed at birth;
– whether the test is common enough within the surrounding population to justify the test;
– whether a simple test exists; whether treating the baby will prevent irreversible damages;
– whether the disease can be missed clinically at birth (in other words, as a follow up to the doctor’s at-birth examination.)
Hospitals commonly perform the blood tests while the baby is still in the pediatric nursery. For babies born at home or away from the hospital, doctors recommend bringing the newborn in for testing no later than the seventh day after birth.
Disease Testing Mandated Everywhere
While states determine the makeup of screening test batteries, federal law requires them all to test for some diseases. According to the U.S. National Newborn Screening and Genetics Resource Center, only four tests are currently mandated by every state, including:
– phenylketonuria (PKU)
– congenital hypothyroidism (CH)
– galactosemia (GAL)
– sickle cell disease (SS, SC etc.).
This list is in addition to the mandatory hearing test, which does not involve the bloodwork. Because PKU was the first screening test to be developed, the battery of screening tests in sometimes still referred to as “the PKU” test, even when many more diseases are tested.
Expanding the Test Battery
With the arrival of special tandem mass spectrometry testing (abbreviated as MS/MS) during the 1990s, the number of feasible tests performed on the blood sample rapidly expanded to include a broader range of diseases and genetic disorders. While not all hospitals will include the more comprehensive battery of tests made possible by MS/MS, private screenings using the advanced equipment have become affordable in recent years.
In 2005, an expert panel assembled by the National Department of Health and Human Services and the March of Dimes released a report listing thirty tests they recommend for every state, including screenings for hypothyroidism, cystic fibrosis, and sickle cell anemia.
Getting More Tests Than Your State Screens For
The tests are usually determined by each state’s Department of Health, according to the criteria listed above. A listing of which states test for which diseases is available at the National Newborn Screening & Genetics Center’s website: https://genes-r-us.uthscsa.edu/sites/genes-r-us/files/nbsdisorders.pdf.
If you’re concerned your baby might not get all the testing you feel is necessary, there are other options to the tests provided by the hospital. Your doctor can recommend a range of choices, including university hospitals, private laboratories, and special clinics. MS/MS testing typically runs about $89 for a complete range of tests. A listing of facilities offering expanded testing can be found at the Save the Babies.
The drawing of blood is virtually instantaneous, and taken from the newborn’s heel as a means of minimizing your baby’s discomfort. Testing is usually done automatically, as a matter of course inside the hospital. In a handful of states, the testing is compulsory – parents have no choice but to allow the testing as a matter of public health. In Maryland, The District of Columbia, and Wyoming, however, hospitals must obtain parental consent before the testing is performed.