As hearing ability affects language and cognitive development, early detection and intervention of congenital hearing defects is very important. We analyzed the result of newborn hearing screening using automated auditory brainstem response and estimated the incidence of congenital hearing defects in newborn infants in Korea.

Hearing screening tests were done on 7,218 newborn infants who were delivered at Cheil General Hospital from July 1, 2004 to June 30, 2005. The first screening test was done on the second day of life with automated auditory brainstem response(AABR) using ALGO^③ Newborn hearing screener(Natus® Medical Incorporated, San Carlos, USA) with 35 dB sound level. The newborn infants who did not pass the initial screening test took the second screening AABR test before discharge from the nursery. Infants who did not pass these screenings at the nursery were followed up at the Department of Otorhinolaryngology, Samsung Seoul Hospital.

Total 7,218 infants(83.3 percent of total 8,664 live births of the Cheil General Hospital) were screened in the nursery, and 55 of them failed to pass the newborn screening. Among 55 infants who were referred, six were lost during follow-up, and 14 were confirmed as hearing impaired. Six of them(42.8 percent) do not have any risk factors for hearing impairment. We can estimate that the incidence of hearing defects is about 1.9-2.8 per 1,000 live births.

Automated auditory brainstem response is an effective tool to screen the hearing of newborn infants. Congenital hearing loss is more frequent than metabolic diseases on which screening tests are available in the newborn period. About 40 percent of infants who have hearing defects do not have any risk factors for hearing impairment. Therefore, universal newborn hearing screening must be recommended to all neonates.