Your Baby's Hearing

Hearing is very important for language, literacy and brain development. Some babies are born with hearing problems — hearing loss is the most common congenital condition (present at birth), more common than all other conditions for which babies are screened. About 3 in 1,000 babies are born profoundly deaf, and another 3 in 1,000 have serious hearing loss. Most hearing-impaired children are healthy and born to hearing parents.

How is hearing loss detected early?

The oto-acoustic emission (OAE) test is the most common newborn hearing screening test. A specialist places a small microphone in your baby's ear, which sends a sound; the echo that comes back is sent to a portable computer that can tell whether the baby heard the sound. The test takes 10 to 15 minutes and can be done even before your baby leaves the hospital — it is recommended that all newborns have their hearing tested.

Without newborn hearing screening, the signs of hearing loss can be very hard to spot. Babies and children who seem alert may actually be using their other senses to understand what's going on around them, or, as they get older, may learn to read lips on their own.

Infants and toddlers — see your doctor if your child

• Was not screened as a newborn — ask for a hearing test.
• Stops babbling (often not noticed until after 12 months of age).
• Does not pay attention or react to loud noises around the house (doorbell, telephone, dog barking).
• Does not turn toward sound by 3–4 months, or toward spoken words by 9 months.
• Has had frequent ear infections and/or fluid draining from the ears.
• Does not say single words by 12 months.
• Does not understand simple phrases unless the speaker is facing them.
• Starts speaking later than usual, or speaks unusually loudly.

Pre-schoolers and school-aged children — see your doctor if your child

• Starts speaking later than usual, or is difficult to understand.
• Needs things repeated.
• Speaks loudly, or turns up the television or radio volume so much it disturbs others.
• Has difficulty following simple multi-step instructions.
• Seems not to be paying attention, especially in a group or noisy setting like child care or school.
• Has trouble learning in school (vision should also be checked).
• Is easily frustrated, more so than other children of the same age.

The signs of hearing loss can be difficult to detect — you may only notice them after the loss has been present for many months or years, because young children are very good at compensating even if they hear very little. Talk to your doctor about any concerns. Though a doctor's office visit alone can't diagnose hearing loss, you can be referred to a centre that can test your child's hearing — even newborn babies can be easily tested.

Why early diagnosis matters

The earlier a hearing problem is found and treated, the easier it is for your child to get the help he needs to communicate and learn. Children diagnosed later, especially after 2 years of age, are more likely to have lifelong problems with language, speech and literacy. Success in school is closely linked to literacy, and literacy is linked to the hearing and speech centres in the brain — to learn to speak, children need to hear, and children who hear and speak learn to read and write more easily.

The first few months of life are critical for developing the brain's speech and language areas; studies show the earlier a baby can hear, the better her language skills will be. Deaf children who are diagnosed early and get the right kind of help can develop just like other children their age. Technologies such as digital hearing aids and cochlear implants allow even profoundly deaf children to hear and speak — even newborns can be fitted with hearing aids, and cochlear implants are being placed in younger and younger infants, ideally before a year of age.