Newborn auditory brainstem evoked responses (ABRs): prenatal and contemporary correlates

A literature review and new data on correlates of newborn auditory brainstem evoked responses (ABRs) are presented. Although there has been documentation of the importance of maturation, pathology, postnatal complications, and sex as determinants of the ABR, few investigators have adopted a multivariate approach, resulting in a confounding of maturation with pathological and other factors. In the present study, the ABR was recorded and the I-V interwave latency at 80 dB was computed for 88 newborns (60 neonatal intensive care unit survivors and 28 low-risk babies). 29 variables describing background characteristics, age, pregnancy and delivery complications, and postnatal illnesses were factor analyzed, and the obtained factors were entered into a stepwise regression. Conceptual age was the strongest predictor of the I-V interwave latency, followed by sex and prenatal obstetric complications, although the correlations obtained were low. We concluded that disorders of the central components of the ABR may be more of prenatal than of postnatal origin. In addition, the I-V interval had low but reliable correlations with 4 of 11 Brazelton scale variables. These data show the usefulness of the ABR for monitoring neurologic function in high-risk neonates and foreshadow its potential usefulness as a predictor of developmental outcome.