Most health authorities test hearing within 24 hours of birth. The doctor tests your baby’s hearing by inserting into her ear a probe that looks like a thermometer and can detect tiny echoes from the eardrum to show that the ear is functioning normally.

If the first test does not show a strong enough response, the doctor will refer your baby for a second screening. This does not necessarily mean that hearing loss is suspected: Conditions at the time of the first test may simply not have been right.
A small proportion of babies are referred for an auditory brainstem response (ABR) test, which can give better information about the hearing. The ABR test is usually carried out at an audiology (hearing) clinic in your local hospital. Sounds are played through earphones placed on your baby’s head, usually when she’s asleep. A computer records how your baby’s ears respond to the sounds. If the ABR responds strongly, your baby’s unlikely to have a hearing loss.
If the test results are abnormal, the doctor will refer your baby for further testing and possibly treatment for conditions such as glue ear. If your baby has deafness, she may be fitted with a hearing aid. If the hearing loss is profound and permanent, she may be assessed for cochlear implants, which can be very effective in helping her to hear.

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