Normal Pregnancy and Voice: A PRISMA-ScR Scoping Review of Laryngeal and Vocal Outcomes.
Abstract
Objective
Pregnancy produces physiologic adaptations that may affect laryngeal tissues, respiratory support for phonation, and voice quality. We performed a scoping review exploring the influence of pregnancy on voice and laryngeal outcomes. DATA SOURCES PubMed, CINAHL, and Web of Science. REVIEW
Methods
A scoping review was conducted per PRISMA-ScR guidelines. Searches of PubMed, CINAHL, and Web of Science yielded 1350 studies screened in Covidence by two reviewers. Of 107 full texts reviewed, 22 met inclusion criteria. We included human studies in which pregnancy was the primary exposure and voice-related outcomes were measured. Pregnancy-specific animal studies were included when modeling mechanisms of laryngeal change.
Results
Twenty-two studies met inclusion criteria and were grouped into domains: acoustic/aerodynamic (n = 16), patient-reported/perceptual (n = 12), physiologic laryngeal (n = 5), mechanistic animal studies (n = 4), singing voice (n = 4), and respiratory (n = 1); several studies contributed to multiple domains. Acoustic measures (fundamental frequency, jitter, shimmer) were generally unchanged, while multiple studies reported reduced maximum phonation time (MPT) during pregnancy. Subjective voice measures tended to worsen, and singer studies reported reduced vocal range and timbre changes. Physiologic studies noted increased vocal fold edema and reduced motility, most prominent in the third trimester. Mechanistic models supported hormone-associated mucosal changes and altered laryngeal protein expression.
Conclusions
The literature on voice changes during pregnancy is limited and heterogeneous, with evidence concentrated in late pregnancy. Pregnancy is more consistently associated with reduced phonatory efficiency and worse perceived voice function than with major acoustic vocal changes. LEVEL OF EVIDENCE N/A.
