Your newborn likely received his or her first hearing test in the maternity ward. It's one of several screening tests that are routinely performed soon after birth. Techniques commonly used are otoacoustic emissions (OAEs) and/or auditory brainstem response (ABR) tests. Rest assured, your baby almost certainly didn't notice a thing.
Early testing is important to determine if intervention is needed to ensure your child’s language and other aspects of development are not impacted by problems with hearing. Beyond the hospital stay, children may be tested for hearing if a doctor or parent notices there may be an issue with processing sound and understanding language. Toddlers can be tested with the use of headphones or in a soundproof booth. The child's reaction to sounds from various directions and at various frequencies is observed, and the resulting data help the audiologist determine if there is a deficiency that needs to be addressed.