Newborn Screening

There are three parts to newborn screening.

Metabolic Screening

• Metabolic screening of the newborn is used to detect metabolic birth defects. (Metabolic refers to chemical changes that take place within living cells during the process of digestion and absorption.) These conditions cannot be seen in the newborn, but if untreated, can cause physical problems, mental retardation and, in some cases, death.  The test requires a sample of blood from your baby and is most accurate if conducted at around the 3rd or 4th day of life.  The blood is collected by sticking your baby’s heel with a lancet and collecting 5 drops of blood on a special test card.  Metabolic screening is mandated by most states. This means that all infants are required to be screened per state law unless a parent or guardian chooses not to for personal or religious reasons and signs an informed consent.

Hearing Screening

• The newborn hearing screen is mandated by most states.  In the first month of life, all infants are to be screened for congenital hearing loss by  a hearing specialist or audiologist.  For this test, your provider places a tiny, soft speaker in your baby’s ear to check how your baby responds to sound.  The automated ABR screening will display a “Pass” or “Refer” response which is recorded and sent into the state agency.  

The National Institute on Deafness and Other Communication Disorders (NIDCD) estimates that 2 or 3 out of every thousand children in the US are born deaf or hard of hearing.  The purpose of early screening is to ensure that all babies with suspected hearing loss have the opportunity to benefit from early intervention that could support language development skills.

Heart Screening

• The heart screening test is called pulse oximetry. It checks the amount of oxygen in your baby’s blood by using a sensor attached to his finger or foot. This test is used to screen babies for a group of heart conditions called Critical Congenital Heart Disease (CCHD).  This screening is done between 24-48 hours postpartum as the baby’s circulation makes the transition to life outside the womb.  I offer this screening at your first postpartum visit.  Depending on the nature of any abnormal results, we can consult with a pediatric cardiologist, refer your baby to your pediatrician, or to the nearest pediatric hospital.

Critical congenital heart defects (CCHD) refer to heart defects that 1% of babies are born with and that require surgical intervention within the first month (or year, depending on the defining organization). About 1 in 100 babies have heart defects, and about 1 in 4 of those with a heart defect have a defect so severe that it needs to be corrected immediately (0.25% of all babies). Only some of these defects will be picked up by prenatal ultrasound, and they may not show up on exam before the baby goes home (or the midwife leaves, in the case of a home birth). Depending on the defect, some babies may be able to compensate with structures that were in place during the fetal period, but begin to go away after the baby is born.