Earlier Is Better to Catch Hearing Loss
When should your child's hearing be tested? Sooner than you think.
Many experts urge hearing tests before newborns leave the hospital, says Judith Gravel, Ph.D., a hearing specialist in Philadelphia. Every year, approximately 1.5 to 3 per 1,000 babies are born in the United States with hearing problems. That translates to as many as 33 babies born every day with hearing impairments. Many states have passed laws requiring hospitals to perform hearing tests on all newborn infants before they leave the hospital.
For years, routine hearing tests took place only when children entered school. But hearing loss can cause serious problems much earlier. "The most significant is the development of language and speech," says Dr. Gravel.
By the age of 6 months, she explains, babies begin to recognize the spoken sounds that are critical for developing language. Poor hearing can hamper that progress for both the spoken and written word. "Often children who have a hearing loss have a great deal of difficulty reading," she says.
Consider having your child tested for hearing loss, especially if he or she has any of the following risk factors:
A two-day (or more) stay in neonatal intensive care
A family history of childhood hearing loss
A family history of certain hereditary or congenital syndromes such as Noonan’s, Waardenburg syndrome, Multiple lentigines syndrome, or Kartagener syndrome
Even without risk factors, parents should remain alert to hearing problems. Some hearing loss gets worse over time. Some hearing loss is stable. Because about 2 to 3 infants out of every 1,000 born have some degree of hearing loss, it is wise to have this checked early.
"If the parents have any concern about the baby's responsiveness to sound, then they ought to have the baby's hearing checked," says Dr. Gravel. "Even very young infants early on are very interested in the sound of a human voice, especially their mother's voice."
At 5 months, infants turn their heads accurately toward sounds. By 10 months, babies should be babbling in multiple syllables. "Babies who hear normally respond even to soft sounds in the environment," she adds.
Recurrent ear infections, which are common in young children, can also delay language development. And Dr. Gravel notes that a newborn can pass a hearing test and still develop hearing problems later in childhood.
Technology to help hearing-impaired children is evolving rapidly. Such children, Dr. Gravel says, generally benefit from some sort of amplification, ranging from digital hearing aids to cochlear implants. Hearing aids help make the sounds louder. Cochlear implants convert sound into a signal that is sent to a receiver. The receiver then sends the signal to the brain. The receiver is a small disk surgically placed under the skin behind the ear.
In all states, she says, "services are out there and available for parents." No child is too young to benefit from seeking help: "You want to do it right away."
Your child is likely to undergo one of these painless, quick and sensitive tests:
* Auditory brainstem responses. Sound is introduced to the baby's ears through tiny headphones while the baby is sleeping. Using electrodes attached to the head, the test records electrical activity generated by the auditory nerve when it's stimulated by this sound.
* Otoacoustic emissions. The normal ear generates faint acoustic signals, sometimes called inner-ear echoes. Although people cannot hear their own emissions, tiny, sensitive microphones placed in the ear canal during the screening can measure the sounds. Infants who can't hear create no emissions.