Effects of sex and gestational age on the auditory brainstem responses among two ears in moderate preterm infants

Abstract Objectives Auditory cortex in each hemisphere mostly receives the sounds from the opposite ear. The present study aimed at the contralateral dominance of auditory brainstem response (ABR) among the ears in preterm neonates by comparing sex and gestational age. Methods Transient Evoked Otoacoustic Emission (TEOAE) and Auditory Brainstem Response (ABR) were recorded at 3 months postconceptional age (PCA). The performance of two ears in ABR was compared. In addition, performance of each ear was analysed in females and males. A comparison of moderate gestational age also was performed. Twenty preterm neonates from 32 to 36 weeks gestational age admitted to the neonatal intensive care unit at Shafizadeh Children’s Hospital were participated. Results No significant asymmetry in ABR absolute latency and inter-peak intervals of right and left ears in preterm infants was noticed. Females and males did not demonstrate statistically significant values in ABR latencies. Moreover, the results of four gestational ages were not statistically different from each other. Conclusion The maturation of the auditory brainstem pathways most likely take places in both hemispheres simultaneously, independent of sex in preterm infants. Changes of gestational age in each month do not impact on the maturation of the auditory brain pathways.