RESUMEN
Background: Non-stress test is the most widely used test to assess fetal status. The presence of beat-to-beat variability is reassuring while its absence is not reassuring
Methods: In this single-blind clinical trial, 213 pregnant women with gestational age of 37 - 41 weeks were randomly allocated into three groups [auditory intervention for mother, auditory intervention for fetus, and control], each containing 71 subjects. The data were analyzed using one-way ANOVA followed by Tukey HSD test and Kruskal-Wallis test. In addition, paired t-test was used to compare each group before and after the intervention
Results: The results showed a significant difference among the three groups regarding beat-to-beat variability of fetal heart rate in the second 10 minutes of the test [P = 0.006]. Besides, the results of Tukey HSD test indicated that this difference was significant between the control group and auditory intervention for mother group [P = 0.004]. Moreover, the results of t-test showed a significant difference in beat-to-beat variability of fetal heart rate between the first and the second 10 minutes of the test in both groups of auditory intervention for mother [P < 0.001] and for fetus [P < 0.001]
Conclusions: Since beat-to-beat variability of the fetal heart rate is indicator of fetal health, music intervention can be used to increase the number of accelerations and reduce false positive results in NST