Positive effects of low intensity recorded maternal voice on physiologic reactions in premature infants

To evaluate the effect of low intensity recorded maternal voice on the physiologic reactions of healthy premature infants in the neonatal intensive care unit (NICU).

Physiologic responses of 20 healthy preterm infants in the NICU of Shariati Hospital, Tehran, were obtained during a 15min intervention including three 5min periods (no-sound control, audio recorded playback of mother's voice, no-sound post-voice). The intervention was presented three times a day for three consecutive days. During each intervention, oxygen saturation (%, OSPR), heart rate (HR), and respiratory rate (RR) were recorded at 1min intervals over the 15min and then averaged over each 5min period, resulting in 3 averages for each variable for each intervention.

Repeated Measures Analysis of Variance were employed to examine each variable separately. Over the three days, comparison of oxygen saturation over each of the three periods (before, during voice, after) revealed an increase in oxygen saturation during the voice period, compared to the pre-voice period, which persisted over the post-voice period; there were no differences between the voice and post-voice periods. Analyses of the HR and RR data showed a decrease in both variables during the voice period compared to the pre-voice period which persisted over the post-voice period. Again, there were no differences between the voice and post-voice periods.

Exposure to low intensity recorded maternal voice has positive effects on the preterm infants 'physiologic responses.