Newborn Hearing Screening
Newborn hearing screening is a noninvasive method used to detect hearing loss in newborns. Since 3 out of every 1000 newborns are born with permanent hearing loss, many of them with no known risk factors for the condition, newborn hearing screening is essential. Once limited to infants considered to be at high risk for hearing loss, such as premature infants, newborn hearing screening is now, although not mandated in every state, nearly universally performed.
Reasons for Newborn Hearing Screening
Newborn hearing loss can greatly affect the development of speech and language, as these skills are developed during the first three years of life. Most hearing screenings are performed before babies leave the hospital or during the following few weeks.
By identifying hearing loss in newborns, early intervention can be provided to help a child develop normal language skills during the critical first years of life. Newborn hearing screening is now performed on the majority of infants before they leave the hospital after birth. This has proven to be extremely important because in the past, before newborn hearing screening became the norm for infants, children with hearing loss often fell behind their peers in language, cognitive, and social skills before being diagnosed with hearing loss. Hearing loss in infancy or childhood often resulted in difficulties later in life, including speech problems, deficient literacy skills, poor academic performance, and, eventually, long-term employment limitations.
Causes of Newborn Hearing Loss
Infant hearing loss may be caused by a variety of factors which may include:
- Congenital defects
- Certain conditions of the mother during gestation, such as diabetes or toxemia
- Middle ear infection, or otitis media
- Acquired hearing loss from other illness or injury
Types of Newborn Hearing Screening
There are two types of screening tests typically performed to assess newborn hearing, both of which are performed while the baby is sleeping. These tests screen for the extent of hearing loss, although other tests may need to be performed to determine the cause of any hearing deficiency. Newborn hearing screenings are designed to assess the functioning of the cochlea, an essential component of the inner ear. The cochlea not only receives but also emits sounds. These sounds, known as otoacoustic emissions, are what the tests measure. The two types of newborn hearing screening tests usually administered are:
Evoked Otoacoustic Emissions Test (OAE)
This test involves placing a soft earpiece in the outer ear. This earpiece makes soft clicking sounds which will normally be echoed back into a microphone when the ears are functioning properly.
Brainstem Auditory Evoked Response (BAER)
This examination involves placing sensors on the forehead and behind each ear while an earphone in the ear emits several soft sounds. The sensors measure the responses of the hearing nerve to these sounds.
If the results of a hearing screening are abnormal, additional testing may be performed to determine the cause of the hearing loss and whether it is permanent. If the infant is determined to have a hearing deficit, hearing aids, speech therapy or surgical repair may be required to help the baby develop normal communication skills.