Baby Hearing Milestones by Age

Yes. The auditory system is functional by 20–24 weeks of gestation. By the third trimester, babies can hear muffled sounds from outside the womb and begin recognizing their mother's voice. This is why newborns prefer the sound of their mother's voice over a stranger's.

The newborn hearing screen uses OAE (otoacoustic emissions) or ABR (auditory brainstem response) testing to check hearing within hours of birth. It detects congenital hearing loss, which affects 1–2 in 1,000 newborns. Early detection (before 6 months) allows intervention before language development windows close.

An inconclusive or failed screening doesn't confirm hearing loss — it means further evaluation is needed. Follow up with an audiologist within 1 month. Many babies who don't pass the newborn screen have normal hearing on follow-up testing.

Signs include: not startling to loud sounds, not turning toward voices, no babbling by 6 months, not responding to name by 7–8 months, limited babbling or speech, or sudden loss of previously present hearing behaviors. Any regression in hearing responses warrants immediate evaluation.

About 1–2 in 1,000 newborns are born with significant hearing loss, making it one of the most common birth conditions. An additional 2–3 per 1,000 develop hearing loss by school age from causes like infections, noise exposure, or progressive genetic conditions.

Depending on the type and degree of hearing loss: hearing aids (even for infants, fitting is possible by 1–2 months), cochlear implants (for severe to profound loss, usually 12 months+), speech-language therapy, and auditory training. The earlier intervention starts, the better the language outcomes.

Recurrent acute ear infections or persistent fluid in the ear (otitis media with effusion) can cause temporary, mild hearing loss that usually resolves. Chronic, untreated middle ear disease can rarely contribute to permanent damage. Prompt treatment of ear infections is important.