Hearing Screening Tests for Newborns
According to the National Institutes of Health (NIH), almost 12,000 babies are born each year in the United States with a hearing impairment. It is estimated that serious hearing loss occurs in about 2 to 3 of every 1,000 newborns. Without screening or testing, hearing loss may not be noticed until the baby is more than 1 year old. If hearing loss is not detected until later years, there will not be the maximum possible stimulation of the brain's hearing centers. This can affect the maturation and development of hearing, and can delay speech and language. Social and emotional development and success in school may also be affected.
Most hearing loss is congenital (present at birth), but some babies develop hearing loss after they are born. Hearing loss is more likely in premature babies, and babies with infections or respiratory problems requiring long-term use of breathing machines, infection, and certain medications.
Because of these risks, many health organizations including the NIH and The American Academy of Pediatrics now recommend universal infant hearing screening. Today, nearly all newborns are screened for hearing loss, which allows earlier treatment to prevent delays in language and development.
Types of testing
There are 2 primary types of hearing screening methods for newborns. These may be used alone or together:
Evoked otoacoustic emissions (EOAE). A test that uses a tiny, flexible plug that is inserted into the baby's ear. Sounds are sent through the plug. A microphone in the plug records the otoacoustic emissions (responses) of the normal ear in reaction to the sounds. There are no emissions in a baby with hearing loss. This test is painless and is usually completed within a few minutes, while the baby sleeps.
Auditory brainstem response (ABR). A test that uses electrodes (wires) attached with adhesive to the baby's scalp. While the baby sleeps, clicking sounds are made through tiny earphones in the baby's ears. The test measures the brain's activity in response to the sounds. As in EOAE, this test is painless and takes only a few minutes.
If the screening tests identify that your child has a hearing loss, further testing is needed. It is recommended that all babies with hearing loss be identified by 3 months of age so that treatment can begin before the baby is 6 months old, an important time for speech and language development.