Hearing tests for babies - identifying deafness

How well can your child hear? Jane Bartlett reports on the test for all newborn babies

Hearing tests employing the latest state-of-the-art technology, are offered to all newborns. Babies are given the minute-long Oto-Acoustic Emission test, within two days of birth. The test involves sending sound into the baby’s ear and measuring the level of sound returned, thus calculating the level of hearing function. It can be adjusted according to the complexity of each case, which means if there are concerns after a test, a more detailed one will be offered.

Early testing means that many children with hearing problems can be identified before they start school. One American study showed that if babies can’t hear well, their communication skills suffer from the age of six months.

It’s estimated that three in every 100 children experience some degree of hearing loss by the time they go to school. It may affect one or both ears, and a child may be able to hear some sounds or nothing at all.

There are basically three types of deafness:

Conductive hearing loss

Sensory hearing loss – malfunction of the inner ear or damage to the auditory nerve. When the nerve is damaged, hearing loss is usually permanent. This type of hearing loss can be genetic, or may be caused by a serious illness like meningitis. It can also occur in the womb, if the mother contracts German measles while she’s pregnant or suffers with severe food poisoning such as salmonella or listeria. Babies born prematurely and those deprived of oxygen at birth may also suffer deafness.

Central Hearing Loss – caused by changes in the auditory centre of the brain, due to injury, disease or a tumour. It can also be hereditary.