Hearing screening by otoacoustic emission is currently done for all newborns in China, usually 2-3 days after birth or before the baby is discharged from the hospital for premature babies. There are some complications early in life, such as hypoxia, jaundice and brain damage, which are risk factors for hearing impairment. Due to the immaturity of preterm babies, some babies who fail the hearing screening before discharge from the hospital need further re-screening, which will be done at the 42-day post-birth check-up. When the baby is three months old, those who are able to do so should go to the local pediatric hearing diagnostic center for an audiological evaluation to allow early detection of hearing impairment and early intervention.