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Updated: Jul 6, 2026

Analysis of Electrocardiograms and Behavior in Mice from Pregnancy to Lactation Period
Published on: April 5, 2024
Effect of pregnancy on the speaking voice
Abdul-Latif Hamdan1, Lorice Mahfoud, Abla Sibai
1Department of Otolaryngology-Head and Neck Surgery, American University of Beirut Medical Center, Beirut, Lebanon. alhamdan@svclb.com
Abstract:
The study aims to investigate the vocal symptoms and acoustic changes in pregnant women pre- and postpartum in comparison to the controls. A total of 25 pregnant women who presented for delivery were enrolled in this study. Twenty-one nonpregnant women were matched as controls. Vocal symptoms such as hoarseness, vocal fatigue, and aphonia were assessed. Acoustic analysis included fundamental frequency (F(0)), habitual pitch, relative average perturbation (RAP), shimmer, noise-to-harmony ratio (NHR), and maximum phonation time (MPT). There were no significant differences in the incidence of vocal symptoms in pregnant women versus controls. However, vocal fatigue was more prevalent in the pregnant group. With respect to the acoustic parameters, there was a significant decrease in the MPT at term. The rest of the variables were comparable. Postpartum, the MPT significantly increased and there was an increase in F(0) and a significant decrease in the voice turbulence index (VTI). Pregnant women have more vocal fatigue and a reduction in MPT compared to the controls. Immediately after delivery, there is a significant increase in MPT.
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