If your baby failed the hearing test given in the hospital a few days after birth, the doctor likely recommended a quick retest within a week or so. If your baby again failed the hearing test, some further testing will likely be required to determine whether hearing damage is actually present or if some other underlying cause is throwing off the results.
Here are a few of the potential next steps if your baby has failed multiple hearing tests.
An Auditory Brainstem Response test uses external electrodes placed on your baby's head to monitor any brain activity that arises in response to sounds that are played. The test, administered by an audiologist like Barth Craig T MA CCC-A, involves both the inner ear and the brain's potential reponse to sound.
Your baby doesn't need to be awake for the test and it won't cause any discomfort. The sounds presented won't vary greatly in volume as this test is more aimed at checking your baby's potential reaction to certain pitches. For example, your baby might have trouble hearing a deep male voice but can otherwise hear fine. Results can lead to further testing of the biological hearing structures or can be a sign that your child will simply need hearing assitance later in life.
If the ABR test still isn't providing answers, there are still a few tests to try.
Cytomegalovirus, or CMV, is a virus that is particularly easy for pregnant women to develop and pass to the baby. It's also possible for a newborn to develop CMV after birth independently of the mother. CMV doesn't have a cure and stays with the baby for the rest of their life. But CMV is also largely asymptomatic or dormant so sufferers often never know they even have a problem.
One of the most common symptoms in babies with CMV is hearing loss. So repeated failures of standard hearing tests might lead your doctor to test for the presence of CMV. The test involves simple blood work that looks for an antibody produced when CMV is present. If your baby tests positive for CMV, the doctor will likely prescribe antiviral medication to reduce the symptoms. This can in turn restore your baby's hearing over time.
Older Child Response Tests
When your baby reaches the age of about six months, it becomes possible to test hearing response in a more interactive way. The doctor might first try a Visual Reinforcement Audiometry test that involves showing your baby pairing sounds with animations to gauge whether your child can respond to the combination of the two. Sometimes, a baby can hear perfectly fine but not respond to sounds unless interested in what's attached to the sound such as music played when an animated mouse bounces across the screen.
Another possible test is Conditioned Play Audiometry, which becomes possible after a year of age. Your child will be assigned a fun task such as throwing a ball whenever a sound is played.