Marked latency change of auditory brainstem response in preterm infants in the early postnatal period

In order to evaluate the influence of extrauterine life on auditory brainstem response in neonates, we performed serial ABR recordings twice a week in 10 preterm infants. A marked decrease of I-III interpeak latency was observed in 7 infants during the first 2 or 3 weeks after birth. Wave I latency also remarkably reduced during this period in 5. These findings were related not to the conceptional age but to the extrauterine age. In 2 infants III-V interpeak latency increased during the first 1 or 2 weeks after birth, and the rate of latency increase seemed to be inversely proportional to that of decrease of I-III interpeak latency.