Sex Hormones & Voice: From Puberty to Gender-Affirming Therapy with Dr Silvia Ciancia

Here is a comprehensive summary and review of the key takeaways from Dr Ciancia’s presentation.

About the Speaker

Dr Silvia Ciancia earned her medical degree from the University of Pisa and completed her paediatric residency at the University of Modena and Reggio Emilia. Her clinical and research trajectory spans Italy, France, Romania, Kenya, Ethiopia, the US, and Belgium (Ghent University Hospital). Specializing in paediatric endocrinology, her work encompasses thyroid disorders, growth challenges, adrenal conditions, pubertal development, and multidisciplinary adolescent gender-affirming care.

1. Endocrine Physiology: How Hormones Target the Larynx

Dr Ciancia opened the session by demystifying the underlying biological mechanisms linking the endocrine system to vocal physiology. Rather than acting purely as systemic messengers, sex hormones bind directly to specific receptors distributed throughout laryngeal structures—including the vocal fold epithelium, lamina propria, vocalis muscle, supraglottic tissues, laryngeal mucosa, and cartilages.

Key physiological highlights include:

• Non-Binary Hormone Biology: Both biological sexes produce androgens (such as testosterone) and oestrogens (such as oestradiol). The primary difference lies in circulating concentration levels, with peripheral tissue conversion driven by enzymes like aromatase.
• The HPG Axis: Sex steroid production is governed by the Hypothalamic-Pituitary-Gonadal (HPG) axis. The hypothalamus secretes Gonadotropin-Releasing Hormone (GnRH), prompting the pituitary gland to release Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH), which then signal the gonads (testes or ovaries) to produce testosterone or oestradiol.

2. Lifespan Vocal Transitions: From Birth to Older Age

The presentation charted the vocal changes experienced at every stage of human development:

• Mini-Puberty & Childhood: A brief activation of the HPG axis occurs shortly after birth ("mini-puberty"), which some literature suggests subtly influences infant cry melodies. The axis then goes silent during childhood. Consequently, prepubertal boys and girls have nearly identical laryngeal structures and high fundamental frequencies (~250–350 Hz).
• Endogenous Puberty: Under the influence of testosterone, male puberty induces marked laryngeal growth: vocal fold lengthening (~1.6 cm), vocal tract expansion (~16.9 cm), increased vocalis muscle mass, and thyroid cartilage remodelling (forming the Adam's apple). This results in a full-octave pitch drop (~120 Hz). Conversely, estrogenic female puberty causes milder structural changes (~1.0 cm vocal fold length, ~14.1 cm vocal tract length), yielding a smaller pitch drop of approximately one-third of an octave (~220 Hz).
• Cyclical Fluctuations & Premenstrual Dysphonia: In females, monthly fluctuations in oestrogen and progesterone alter tissue hydration, vocal fold viscosity, and vascularization. During the late luteal phase, high progesterone can cause mucosal edema and fluid retention, manifesting in premenstrual dysphonia (hoarseness, reduced vocal range, breathiness, and pitch instability).
• Aging (Menopause & Andropause): Oestrogen drop during menopause leads to mucosal thinning, reduced lubrication, loss of elasticity, and breathiness (which Hormone Replacement Therapy can attenuate). In men, age-related testosterone decline (andropause) causes vocal fold atrophy, tissue stiffness, reduced endurance, and a slight rise in fundamental frequency.

3. Gender-Affirming Care Protocols for Youth

Dr Ciancia provided essential context regarding clinical care pathways for transgender and gender-diverse youth, tracing the evolution from early psychological frameworks to the world-standard Dutch Protocol. Modern adolescent care relies on a multidisciplinary team combining child psychologists, pediatric endocrinologists, gynaecologists, social workers, and speech-language professionals.

Medical management typically proceeds in two distinct pharmacological phases:

1. Phase 1 — Puberty Suppression (Fully Reversible): Utilizes GnRH analogues (or progestins/anti-androgens in later stages). GnRH analogues pause hypothalamic signalling, blocking endogenous hormone production. This halts unwanted secondary sex characteristics, alleviates psychological distress, and buys crucial time for identity exploration.
2. Phase 2 — Gender-Affirming Hormones (Partially Irreversible): Typically initiated around ages 15–16 with gradually escalating doses to mimic pubertal progression. Transgender males receive testosterone, while transgender females receive oestradiol.

1. Key Research Insights: Vocal Outcomes in Transgender Youth

A core highlight of the presentation was Dr Ciancia’s cross-sectional research conducted at Ghent University Hospital, evaluating long-term vocal outcomes (5–10 years post-treatment) in young adults who began medical transition during adolescence:

• Transgender Men (Transmasculine): Exogenous testosterone is remarkably effective at lowering fundamental frequency. Trans men achieved median pitch levels and pitch ranges that fully aligned with cisgender male controls, regardless of the timing or type of puberty suppression used.
• Transgender Women (Transfeminine): Oestradiol does not reverse structural laryngeal masculinization once testosterone-driven pubertal changes have taken place. Trans women who initiated puberty block late exhibited fundamental frequency values situated between cisgender male and cisgender female averages.
• The Clinical Importance of Timing: Research confirms that early puberty suppression (at Tanner Stage 2) prevents laryngeal masculinization entirely. Trans girls starting early maintained fundamental frequencies in the feminine range (~200+ Hz) and reported significantly lower long-term vocal discomfort.

5. Q&A & Clinical Discussion Highlights

The session concluded with an interactive Q&A session with the audience:

• Psychoeducation & Youth Voice Satisfaction: Transgender voice specialist speech therapist Sarah Rabin shared reflections from clinical practice, observing that young people often exhibit substantial increases in vocal satisfaction and communicative confidence even with modest objective pitch changes. Dr Ciancia agreed, reinforcing the importance of setting realistic expectations when voice training occurs after pubertal changes have already occurred.
• Vocal Range & Agility in Transgender Male Singers: Vocal educator Jennifer Myers queried challenges around restricted vocal range observed in trans male college singers taking testosterone. Dr Ciancia noted that synthetic testosterone absorption, individual metabolic sensitivity, and structural dynamics (increased vocal fold mass within fixed cartilaginous boundaries) can contribute to individual variation, highlighting the need for flexible assessment frameworks in vocal pedagogy.

Final Thoughts

Dr Ciancia’s presentation underscored that endocrine science is an essential foundation for modern voice pedagogy and therapy. Understanding the biological mechanisms of sex hormones equips voice professionals to provide empathetic, realistic, and evidence-based support for all singers and speakers across their lifespan.