What is the recommended hearing screening protocol for infants?

Recommended Hearing Screening for Infants

All infants should undergo universal hearing screening using physiologic measures (OAE or automated ABR) before hospital discharge, ideally after the first 24 hours of life, with screening completed by 1 month of age at the latest. 1, 2

Screening Protocol by Population

Well-Infant Nursery (Level I)

• Screen with otoacoustic emissions (OAE) as the initial test before discharge, preferably after 24 hours to minimize false positives from middle ear fluid, vernix, or cerumen 2, 3
• Use a two-stage protocol: if the infant fails the initial OAE, perform a second OAE screening before discharge or refer for outpatient rescreening within 1 month 1, 4
• If the infant fails both OAE screenings, refer directly for comprehensive audiological evaluation including diagnostic ABR testing by 3 months of age 1, 4

NICU Population (Level II/III with ≥2 days admission)

• Screen exclusively with automated ABR technology, not OAE 1, 2
• This is critical because NICU infants are at 10-20 times higher risk for neural hearing loss (auditory neuropathy/auditory dyssynchrony), which OAE cannot detect 1, 2
• If the infant fails automated ABR in the NICU, refer directly to an audiologist for diagnostic evaluation rather than outpatient rescreening 1, 4

Timeline Benchmarks (1-3-6 Rule)

• Screening by 1 month of age 1
• Diagnostic audiological evaluation completed by 3 months of age for those who fail screening 1, 4
• Intervention (hearing aids, early intervention services) initiated by 6 months of age 1, 4

Critical Technical Specifications

OAE Testing Details

• Place a small probe with microphone in the ear canal to deliver clicks or tone bursts and measure cochlear acoustic emissions 2
• Test each ear separately for ear-specific results 2
• Automated screeners provide pass/fail results without requiring audiologist interpretation 2
• Major limitation: OAE only tests cochlear function, not neural pathways or cortical processing—it cannot detect auditory neuropathy 1, 2, 5

ABR Testing Details

• Use automated ABR with clear pass/fail criteria to eliminate operator interpretation bias 1
• For NICU infants, ABR detects both cochlear and neural hearing loss 1
• Diagnostic ABR (when indicated) should include frequency-specific ABR with air-conducted tone bursts, click-evoked ABR with condensation and rarefaction stimuli, and tympanometry with 1000-Hz probe tone 4, 5

Understanding False Positives and Follow-Up Rates

• Only 2% of infants who fail OAE screening in well-infant populations actually have sensorineural hearing loss 2, 4
• Approximately 6.7% of infants who fail in-hospital screening are eventually diagnosed with bilateral hearing loss 4
• 23% of infants with permanent hearing loss at 8-12 months will have passed a two-stage OAE/ABR protocol because most automated ABR equipment is designed to detect moderate or greater hearing loss and misses mild losses 6, 7
• Loss to follow-up occurs in 13-31% of infants who fail initial screening, representing a major system failure 2, 4

Risk Factors Requiring Enhanced Surveillance

Even if an infant passes newborn screening, the following risk factors mandate at least one diagnostic audiology assessment by 24-30 months of age: 1, 4

• NICU admission ≥2 days
• Family history of childhood sensorineural hearing loss
• Congenital infections (toxoplasmosis, syphilis, rubella, cytomegalovirus, herpes)
• Craniofacial abnormalities including ear tags, pinna malformations, or ear canal abnormalities 5
• Syndromes associated with hearing loss (Usher, Waardenburg)
• Hyperbilirubinemia requiring exchange transfusion 4
• Culture-positive sepsis 4

Common Pitfalls to Avoid

• Do not rely solely on OAE for NICU infants—this will miss neural hearing loss entirely 1, 2
• Do not delay diagnostic evaluation beyond 3 months for infants who fail screening, as intervention before 6 months is critical for language development 4, 5
• Do not assume a passed newborn screen eliminates the need for ongoing surveillance—some hearing loss is delayed-onset or progressive, and mild losses may be missed 1
• Do not screen before 24 hours of life unless medically necessary for early discharge, as false positive rates are significantly higher 2, 3
• Be prepared to provide reassurance to parents of infants with false-positive results, as 3-14% experience significant anxiety even after normal follow-up 2, 4

Quality Control Requirements

Any screening program must include: 1

• Well-maintained equipment with regular calibration
• Thoroughly trained staff
• Systematic parent education about benefits and limitations
• Protocols ensuring infants with positive screens receive appropriate follow-up
• Data reporting to state EHDI (Early Hearing Detection and Intervention) coordinators 1