In the first few years of life, hearing is a critical part of kids' social, emotional,
and cognitive development. Even a mild or partial hearing loss can affect a child's
ability to develop speech and language properly.
The good news is that hearing problems can be overcome if they're caught early
— ideally by the time a baby is 3 months old. So it's important to get your
child's hearing screened early and checked regularly.
Causes of Hearing Loss
Hearing loss is a common birth defect, affecting about 1 to 3 out of every 1,000
babies. Although many things can lead to hearing loss, about half the time, no cause
Hearing loss can occur if a child:
was born prematurely
stayed in the neonatal intensive care unit (NICU)
had newborn jaundice with bilirubin level high enough to require a blood transfusion
was given medications that can lead to hearing loss
was exposed to very loud sounds or noises, even briefly
When Should Hearing Be Evaluated?
Newborn hearing screening identifies most children born with a hearing loss. But
in some cases, the hearing loss is caused by things like infections, trauma, and damaging
noise levels, and the problem doesn't emerge until later in childhood. Researchers
believe that the number of people who have hearing loss doubles between birth and
the teen years. So it's important to have kids' hearing checked regularly as they
Your newborn should have a hearing screening before being discharged from the hospital.
Every state and territory in the United States has now established an Early Hearing
Detection and Intervention (EHDI) program; the program identifies every child with
permanent hearing loss before 3 months of age, and provides intervention services
before 6 months of age. If your baby doesn't have this screening, or was born at home
or a birthing center, it's important to have a hearing screening within the first
3 weeks of life.
If your baby does not pass the hearing screening, it doesn't necessarily mean there's
a hearing loss. Because debris or fluid in the ear can interfere with the test, it's
often redone to confirm a diagnosis.
If your newborn doesn't pass the initial hearing screening, it's important to get
a retest within 3 months so treatment can begin right away. Treatment for hearing
loss can be the most effective if it's started before a child is 6 months old.
Kids who seem to have normal hearing should continue to have their hearing evaluated
at regular doctors' appointments. Hearing tests are usually done at ages 4, 5, 6,
8, and 10, and any other time if there's a concern.
But if your child seems to have trouble hearing, if speech development seems abnormal,
or if your child's speech is difficult to understand, talk with your doctor.
Symptoms of a Hearing Loss
Even if your newborn passes the hearing screening, continue to watch for signs
that hearing is normal. Some hearing milestones your child should reach in the first
year of life:
Most newborn infants startle or "jump" to sudden loud noises.
By 3 months, a baby usually recognizes a parent's voice.
By 6 months, a baby can usually turn his or her eyes or head toward a sound.
By 12 months, a baby can usually imitate some sounds and produce a few words,
such as "Mama" or "bye-bye."
As your baby grows into a toddler, signs of a hearing loss may include:
limited, poor, or no speech
seems to need higher TV volume
fails to respond to conversation-level speech or answers inappropriately to speech
fails to respond to his or her name or easily frustrated when there's a lot of
Types of Hearing Loss
Conductive hearing loss is caused by blockage in the transmission
of sound to the inner ear. Ear infections are the most common cause of this type of
hearing loss in infants and young children. This loss is usually mild, temporary,
and treatable with medicine or surgery.
Sensorineural hearing loss can happen when the sensitive inner
ear (cochlea) has damage or a structural problem, though in rare cases it can be caused
by problems with the auditory cortex, the part of the brain responsible for hearing.
Cochlear hearing loss, the most common type, may involve a specific part of the cochlea
such as the inner hair cells, outer hair cells, or both. It usually exists at birth,
and can be inherited or come from other medical problems, though sometimes the cause
is unknown. This type of hearing loss is usually permanent.
The degree of sensorineural hearing loss can be:
mild (a person
cannot hear certain sounds)
person cannot hear many sounds)
severe (a person
cannot hear most sounds)
person cannot hear any sounds)
Sometimes the loss is progressive (gets worse over time) and sometimes unilateral
(one ear only).
Because the hearing loss can get worse over time, audiologic testing should be
repeated later on. Although medicines and surgeries cannot cure this type of hearing
loss, hearing aids can help children hear better.
Mixed hearing loss happens when a person has both conductive and
sensorineural hearing loss.
Central hearing loss occurs when the cochlea is working properly,
but other parts of the brain are not. This rarer type of hearing loss is more difficult
Several methods can be used to test hearing, depending on a child's age, development,
and health status.
During behavioral tests, an audiologist carefully watches a child respond to sounds
like calibrated speech (speech that is played with a particular volume and intensity)
and pure tones. A pure tone is a sound with a very specific pitch (frequency), like
a note on a keyboard.
An audiologist may know an infant or toddler is reponding by his or her eye movements
or head turns. A preschooler may move a game piece in response to a sound, and a gradeschooler
may raise a hand. Children can respond to speech with activities like identifying
a picture of a word or repeating words softly.
Other Tests to Evaluate Hearing
If a child is too young to get behavioral hearing testing, or has other medical
or developmental problems to prevent this type of test, doctors can check for hearing
problems by looking at how well the ear, nerves, and brain are working.
Auditory brainstem response (ABR) test
For this test, tiny earphones are placed in the ear canals and small electrodes
(sensors which look like small stickers) are placed behind the ears and on the forehead.
Usually, clicking sounds are sent through the earphones, and the electrodes measure
the hearing nerve's response to the sounds.
Young infants under 6 months can sleep for the entire test, but older infants may
need sedation for this test. Older cooperative kids can do this testing in a silent
environment while they're visually occupied.
Normal hearing has a certain appearance when test results are measured on a chart.
Because of this, a normal ABR suggests that a baby's inner ear and lower part of the
auditory system (brainstem) are working normally for typical speech. An abnormal ABR
may be a sign of hearing loss, but it may also be due to some medical problems or
Auditory steady state response (ASSR) test
This test is similar to the ABR, though an infant usually needs to be sleeping
or sedated for the ASSR test.
Sound passes into the ear canals, and a computer picks up the brain's response
to the sound and automatically decides whether hearing loss is mild, moderate, severe,
or profound. This ASSR test has to be done with (and not instead
of) ABR to check for hearing.
Central auditory evoked potential (CAEP) test
This test is similar to the ABR, and uses the same tiny
earphones and small electrodes. This CAEP test allows the audiologist to see if the
pathways from the brainstem to the auditory cortex are working properly. The audiologist
may recommend a CAEP test for some specific types of hearing loss. This test can be
done at any age and does not require participation from the child.
Otoacoustic emissions (OAE) test
A sleeping infant or an older child who may be able to sit quietly can do this
quick test. A tiny probe is placed in the ear canal, then many pulsing sounds are
sent and the probe records an "echo" response from the outer hair cells in the inner
ear. These recordings are averaged by a computer.
A normal recording suggests that the outer hair cells are working well. But in
some cases, a hearing loss may still happen if other hearing pathways are not working
Hospitals use ABR or OAE to screen newborns. If a baby fails a screening, the test
is usually repeated. If the screening is failed again, the baby is sent to an audiologist
for a full hearing evaluation.
Tympanometry is not a hearing test but a procedure that can show how well the eardrum
moves when a soft sound and air pressure are introduced in the ear canal. It's helpful
in identifying middle ear problems, such as fluid collecting behind the eardrum.
A tympanogram puts the tympanometry results into a graph. A "flat" line on a tympanogram
may indicate that the eardrum can't move, while a "peaked" pattern usually suggests
that the ear drum is moving normally. Doctors who do this exam should also do a visual
ear examination and see the ear drum.
Middle ear muscle reflex (MEMR)
The MEMR (also called acoustic reflex test) tests how well the ear responds to
loud sounds by evoking a reflex. In a healthy ear, this reflex helps protect the ear
against loud sounds.
For the MEMR, a soft rubber tip is placed in the ear canal. A series of loud sounds
are sent through the tips into the ears and a machine records whether the sound has
triggered a reflex. Sometimes the test is done while the child is sleeping.
Who Performs Hearing Tests?
A pediatric audiologist specializes in testing and helping kids with hearing loss
and works closely with doctors, teachers, and speech/language pathologists.
Audiologists have a lot of specialized training. They have master's or doctorate
degrees in audiology, have performed internships, and are certified by the American
Speech-Language-Hearing Association (CCC-A) or are Fellows of the American Academy
of Audiology (F-AAA).
Hearing Aids and Other Interventions
While medical treatments and surgery can help people with certain types of hearing
loss, hearing aids are the main treatment for sensorineural hearing loss. The
most common type of hearing loss involves outer hair cells that do not work properly.
Hearing aids can make sounds louder and overcome this problem.
A hearing aid has three basic
parts: the microphone, amplifier, and receiver. Settings can be customized to make
certain sounds louder.
Some hearing aid styles are worn on the body while others fit behind the ear or
in the ear. If regular hearing aids can't be used — as in certain types of conductive
hearing loss — specialized hearing aids that attach to the skill bone can send
sound waves directly to the cochlea.
No single style or manufacturer is best — your doctor will help you choose
a hearing aid based on your child's needs. Most kids with bilateral hearing loss
(in both ears) wear two hearing aids.
Because they are so technology-heavy, hearing aids are expensive. Unfortunately,
health insurance companies do not usually cover hearing aids, although several states
now require that insurance cover at least part of their cost. Talk to your child's
doctor to look for financial assistance options for hearing aids.
A specialized amplification device called an FM system (sometimes called "auditory
trainers") may help kids in school. These systems have a microphone that a teacher
can speak into and a receiver help by the child, which can send the sound to the ears
or directly to a hearing aid. They can work well in the classroom to improve hearing
in group or noisy environments and also can be fitted for personal or home use.
Other assistive listening or alerting devices may help older kids.
In addition to hearing aids or FM systems, hearing rehabilitation may include auditory
or listening therapy and speech (lip) reading. Technology is improving all the time,
so ask your doctor about newer tools available to help aid a child's communication.
A cochlear implant is a surgical treatment for hearing loss; this device doesn't
cure hearing loss, but is a device that gets placed into the inner ear to send sound
directly to the hearing nerve. It can help children with profound hearing loss who
do not benefit from hearing aids.