Objective: To evaluate whether the puberty-like sex hormone surge during the first months of life mini-puberty affects fundamental frequency fo in infant crying as one would derive from hormone influences on voice in adults. Study design: Populational prospective study. Participants: Twenty healthy normal-hearing infants nine boys were recruited for participation.
Methods: Spontaneously uttered cries were collected from each infant at 8 weeks of age. The cries were acoustically analyzed for mean fo and fo range. No indication for a T influence on fo features was found at this age. Although girls showed a slightly higher mean E2 concentration than boys did, the observed differences in cry fo range were judged to be reflective of an infant's serum concentration of E2 rather than a sex-based difference.
Conclusion: In the absence of laryngeal size differences between female and male infants, the result was interpreted as indicative of an E2 influence on viscoelastic properties of the vocal folds. In our opinion, the investigation of young infants' vocalizations during the early postnatal surge of sex steroids mini-puberty may advance our understanding of the mechanisms mediating average sex differences in vocal development and early communication.
Keywords: cry; fundamental frequency; infant; sex differences; sex hormones. Published by Elsevier Inc. All rights reserved. Abstract Objective: To evaluate whether the puberty-like sex hormone surge during the first months of life mini-puberty affects fundamental frequency fo in infant crying as one would derive from hormone influences on voice in adults. Publication types Comparative Study.
