For most parents, the newborn period is a time of profound joy, incredible challenges, and LOTS of questions. As pediatricians, some of the questions we are frequently asked are related to a simple blood test done on all infants in Washington State. Commonly referred to as the “newborn screen” or “NBS”, “PKU”, or “newborn metabolic testing”, this test checks for several congenital disorders that are rare but can be life-threatening.
Often parents want to know:
What does the test involve? The newborn screen is done by pricking the heel of the infant at around 24 hours of age, then collecting a few drops of blood onto a piece of test paper. This is dried and then sent to the state lab, where the testing is performed. Because some of the conditions may take several days to show up, the test is repeated at 7-14 days old (usually by your primary care doctor; it can also be done in the hospital if the baby is still there for any reason).
Does it hurt? The needle prick is performed by trained nurses and is done quickly. It may feel similar to pricking your finger to test blood sugar. And you can significantly decrease the discomfort of the quick poke by breastfeeding your baby during or immediately after the test!
Why do we need this? The diseases we check for are typically rare, but if undiagnosed and untreated can cause a variety of complications, including blindness, poor growth, brain damage, and even death. The reason that testing every baby is essential is that babies with these conditions can look and act perfectly healthy even while the disease is damaging their bodies, until they get so sick they need to be hospitalized or have permanent damage. Starting treatment as early as possible can prevent many of the complications.
What are you testing for? The ...