A: Janice, you're correct that many hospitals have started to offer routine newborn hearing tests over the past 5-10 years. Before this policy started, most children with hearing loss were not diagnosed until 1-3 years of age when they were already showing signs of speech problems. Then researchers made an important finding: when children born with hearing loss were diagnosed in the newborn period and received intervention services before 6 months of age, they were likely to develop normal language and learning skills; but if their diagnosis and intervention were delayed, they were more likely to have developmental and language delays. For this reason, hospitals have begun to test babies' hearing in the newborn nursery. Parents should ask the hospital whether they offer the newborn hearing test; if not, talk with your baby's doctor about arranging to have it done within the baby's first couple of months.

Although most newborns have normal hearing, 2-3 out of every 1,000 babies are born with hearing loss. The hearing loss may be mild to severe, in one or both ears, and temporary or permanent. Approximately one-half of babies with hearing loss have a risk factor for it (e.g., other family members with hereditary hearing loss, serious infection during pregnancy, premature birth, or face or skull deformities), but one-half do not have any risk factors. Although parents think they would be able to recognize if their baby had problems hearing, this is often not true. Many babies with hearing loss startle with loud sounds and even begin babbling normally. Therefore, the only way to detect newborn hearing loss is with the hearing tests.

There are two standard newborn hearing tests—they both take about 5-10 minutes, are painless, and can be done while your baby is sleeping or lying still. In the auditory brainstem response test, headphones placed on your baby play tones or clicks into her ears, and electrode wires placed on your baby's head measure her brain's response to the sounds. In the otoacoustic emissions test, small probes placed in your baby's ear canals play tones or clicks and record the echoes from your baby's ears.

Most babies pass the hearing test, and then they just need the routine check-ups with the doctor at well-baby visits. If a baby does not pass the newborn hearing test, it does not mean that he has hearing loss since these quick screening tests are not perfect. But a more complete medical and hearing evaluation should be arranged through the baby's doctor within the first couple of months. If this evaluation shows that the baby has hearing loss, then parents should work with the child's doctor, the audiologist, ear/nose/throat doctor, and your local early intervention program to get the help the baby needs.