Pulse Oximetry Screening


A pulse oximetry screen is a noninvasive (and painless) test performed on newborn babies to determine the level of oxygen in their blood. This test uses rays of light of different wavelengths to measure the percent of hemoglobin (the part of blood that carries oxygen) that’s filled with oxygen. Normally, a newborn baby should have an oxygen saturation level that is greater than 95%. Screening using pulse oximetry can detect some infants with congenital heart disease (CHD) who otherwise may go undetected for a while.

There are some congenital heart defects that cause a newborn baby to have lower oxygen saturation in the blood after birth. It often can be difficult to determine if a baby has cyanosis (a bluish discoloration of the skin due to poor oxygen content of the blood) just by looking at the baby after birth.

Why is pulse oximetry testing important?

CHD affects about 40,000 U.S. births per year.1 Some congenital heart defects don’t show signs within the first days or even weeks of life. Sometimes, babies with significant CHD may not have a heart murmur after birth. Therefore, some babies may not show signs of significant CHD until after they become very sick. If healthcare providers discover a heart problem before a baby becomes ill, then the baby will have a better chance to do well with any necessary surgeries or procedures. Early diagnosis of the heart problem may also prevent damage to other organs that may occur when a baby becomes sick due to CHD.

While pulse oximetry screening cannot rule out all forms of CHD, it’s a good starting point for evaluating many serious types of congenital heart defects. In 2011, the U.S. Department of Health and Human Services (HHS) recommended that pulse oximetry screening should be included in the routine evaluation that all newborn babies undergo before they’re discharged from the hospital after birth.2 More and more states are adopting this test as a routine procedure to be done on all newborn babies before they go home from the hospital.

Baby and stethoscope

Children's Heart Health

Information for parents of children with pediatric heart conditions. Read more about conditions, tests, and treatments for congenital heart disease.