Objective: While it is known that human voices change over time due to hormonal and anatomical factors such as puberty and menopause, the impact of a professional singing career on these changes remains poorly understood. This study aims to quantify changes in acoustic features of popular female singers’ voices by comparing performances of the same songs over a decade apart, providing insights for laryngologists to differentiate between normal and pathological voice changes and guide singers in maintaining vocal health through repertoire adjustments.

Methods/Design: The cohort for analysis included popular professional cisgender female singers from different genres and generations with over a decade of publicly available music since age 18; they were selected based on their available high-quality videos of live performances at least 10 years apart. Recordings were passed through the Ultimate Vocal Remover application to isolate the singer’s voice, and a prolonged vowel from each performance of at least 2 seconds duration was passed through Praat software for acoustic analysis. Fundamental frequency (f0), f0 standard deviation (f0SD), jitter (local), shimmer (local), and harmonics-to-noise ratio (HNR) were calculated for the prolonged vowel.

Results: Performances spaced an average of 12.6 years apart (SD = 3.9), were analyzed for ten singers. Five singers (50%) lowered the key of their song by at least a semitone in the later performance. The mean duration of each sustained vowel analyzed was 3.3 seconds (SD = 1.0). Acoustic parameters increased across all singers: f0SD by 1.69% (SD = 2.77%), jitter by 0.52% (SD = 1.19%), shimmer by 0.39% (SD = 0.99%), and HNR by 0.18% (SD = 0.65%). Although increased jitter and shimmer suggest reduced voice stability, these changes were not statistically significant.

Conclusions: Struggles to perform repertoire consistently over time can be concerning for professional singers, as their voice is their livelihood. This study suggests that lowering repertoire by a semitone is a common practice among professional singers, even before menopause. No significant changes were observed in the measured acoustic features; these findings indicate that singers experiencing changes in jitter, shimmer, or HNR should be evaluated for pathological changes to guide appropriate intervention.