In 2016, 85.9% of babies born in the Iran had their hearing screened in the first few weeks of life. The primary purpose of newborn hearing screening is to identify newborns who are likely to have hearing loss and who require further evaluation. A secondary objective is to identify newborns with medical conditions that can cause late-onset hearing loss and to establish a plan for ongoing monitoring of their hearing status. Infants who do not pass the newborn hearing screening (and/or rescreening) are referred immediately for a comprehensive audiologic evaluation, with a goal of having hearing loss confirmed by 3 months of age. Passing a screening does not mean that a child has normal hearing across the frequency range.
Two different types of hearing screening tests are used to screen hearing in babies: Automated Auditory Brainstem Response (AABR)—This test measures how the hearing nerve responds to sound. Clicks or tones are played through soft earphones into the baby's ears. Three electrodes placed on the baby's head measure the hearing nerve's response. Otoacoustic Emissions (OAE)—This test measures sound waves produced in the inner ear. A tiny probe is placed just inside the baby's ear canal. It measures the response (echo) when clicks or tones are played into the baby's ears. Both tests are quick (about 5 to 10 minutes), painless, and may be done while your baby is sleeping or lying still. One or both tests may be used. The Infant hearing screening systems are the most cost effective, complete, and easy-to-use infant hearing screeners. These systems offer hearing and medical professionals a choice of automated ABR screening, OAE screening, or both. These devices are portable, simple to operate and does not require special technical skills or interpretation of results by the device operator.