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Female-to-male gender dysphoric individuals rarely access medical services for voice problems arising out of hormonal treatment leading to “voice reassignment”. The aim of this study was a close monitoring of voice deepening in the first year following the commencement of testosterone treatment. Voice recordings from nine female-to-male (FTM) were analyzed with Praat software and values for speaking fundamental frequency (SFF) were calculated. Audio recordings were made prior to and within the first year (mean 55.2 weeks) of testosterone treatment at a mean of 35.4 different time points. The values for speaking fundamental frequency were compared with values taken from 21 biological men with healthy voices. The 10th to 90th percentile range of FTM overlapped with those of biological men after about 36 weeks. The mean SFF change was a decrease of 8.78 seminotes at week 52 and at this point in time no significant difference between SSF in FTM and biological men was found. Testosterone treatment led to significant voice deepening within the first year with the degree of change decreasing over time. Mean SFF change in the first year was almost a sixth and thus less than one octave but nonetheless reached an SFF comparable with biological men.
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Voice deepening under testosterone treatment in female-to-male
gender dysphoric individuals
Dirk Deuster
Peter Matulat
Arne Knief
Michael Zitzmann
Ken Rosslau
Michael Szukaj
Antoinette am Zehnhoff-Dinnesen
Claus-Michael Schmidt
Received: 22 March 2015 / Accepted: 26 November 2015 / Published online: 9 December 2015
ÓSpringer-Verlag Berlin Heidelberg 2015
Abstract Female-to-male gender dysphoric individuals
rarely access medical services for voice problems arising
out of hormonal treatment leading to ‘‘voice reassign-
ment’’. The aim of this study was a close monitoring of
voice deepening in the first year following the com-
mencement of testosterone treatment. Voice recordings
from nine female-to-male (FTM) were analyzed with Praat
software and values for speaking fundamental frequency
(SFF) were calculated. Audio recordings were made prior
to and within the first year (mean 55.2 weeks) of testos-
terone treatment at a mean of 35.4 different time points.
The values for speaking fundamental frequency were
compared with values taken from 21 biological men with
healthy voices. The 10th to 90th percentile range of FTM
overlapped with those of biological men after about
36 weeks. The mean SFF change was a decrease of 8.78
seminotes at week 52 and at this point in time no significant
difference between SSF in FTM and biological men was
found. Testosterone treatment led to significant voice
deepening within the first year with the degree of change
decreasing over time. Mean SFF change in the first year
was almost a sixth and thus less than one octave but
nonetheless reached an SFF comparable with biological
Keywords Voice Transsexualism Female-to-male
Testosterone Sex reassignment procedure
Gender dysphoria is characterized by distress in an individual
and refers to an incongruence between the sex assigned to the
person at birth and their genderidentity [1]. Accordingto ICD-
10, where the term ‘‘transsexual’’ is used, these individuals
‘desire to live and be accepted as a member of the opposite
sex’’ [2]. Cross-sex hormonal treatment with testosterone in
female-to-male (FTM) gender dysphoric individuals causes
various bodily changes including a deepening of the voice
with an expected onset after 3–12 months and an expected
maximum effect after 1–2 years [3,4]. This ‘voice reas-
signment’’ may explain why FTM rarely access medical ser-
vices because of voice problems and the consequent lack of
standard values for voice change as well as the disparity in
voice research—the vast majority of studies concerning voice
physiology, pathology, and therapy regarding transsexual
persons investigated male-to-female (MTF) gender dysphoric
individuals’ voices.
Previous prospective studies of voice deepening in FTM
only investigated individual cases. Van Borsel et al.
reported on two female-to-male transsexuals and showed a
significant lowering of voice mean fundamental frequency
(F0) within 12 and 13 months, respectively. In both par-
ticipants, their voices deepened by less than one octave [5].
Damrose demonstrated a case of one female-to-male
transsexual semi-professional singer and detected a pro-
found reduction of F0 within 3–4 months after starting
androgen treatment [6].
Although an exact calculation is difficult because of the
examination intervals used, the progression of voice
&Dirk Deuster
Department of Phoniatrics and Pedaudiology, University
Hospital Muenster, Kardinal-von-Galen-Ring 10,
48149 Mu
¨nster, Germany
Centre for Reproductive Medicine and Andrology, University
Hospital Muenster, Mu
¨nster, Germany
Psychiatric Practice, Am Rohrbusch 56, 48161 Mu
Eur Arch Otorhinolaryngol (2016) 273:959–965
DOI 10.1007/s00405-015-3846-8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... and stable within-participant reductions in f o after a minimum of ~ 3-4 months on T therapy [32][33][34][35] . Accordingly, participants typically perceived their own voices to be lower in pitch 32 and participants with lower f o reported a higher likelihood of being perceived as male over the phone 35 . ...
... Research suggests that 50% of listeners can detect shifts as low as 1.2 semitones (e.g., 7 Hz for a 100 Hz voice 42 ); therefore, these changes likely have a strong impact on perception of gender. Overall, the current findings are consistent with previous results documenting substantial changes in f o with T therapy in transmen [32][33][34][35][36] and are suggestive of putative anatomical changes resulting from the action of T on the lengthening and thickening of vocal folds, similar to those occurring during puberty in natal males [19][20][21][22][23][24] . To understand the nature of these ...
... This motivates development of additional treatments, such as behavioral therapy, to increase objective speech masculinity by increasing vocal tract length 48 . Previous studies on transmen's speech changes have shown that most changes have occurred prior to 9 months of continuous T therapy [32][33][34][35]49 ; however, these studies did not examine changes in estimated VTL. This study is the first, to our knowledge, to demonstrate statistical differences in VTL between samples of transmen and cisgender speakers [see Cler et al. 43 for a single, detailed case study and Papp 44 for an unpublished dissertation]. ...
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Voice is one of the most noticeably dimorphic traits in humans and plays a central role in gender presentation. Transgender males seeking to align internal identity and external gender expression frequently undergo testosterone (T) therapy to masculinize their voices and other traits. We aimed to determine the importance of changes in vocal masculinity for transgender men and to determine the effectiveness of T therapy at masculinizing three speech parameters: fundamental frequency (i.e., pitch) mean and variation ( f o and f o -SD) and estimated vocal tract length (VTL) derived from formant frequencies. Thirty transgender men aged 20 to 40 rated their satisfaction with traits prior to and after T therapy and contributed speech samples and salivary T. Similar-aged cisgender men and women contributed speech samples for comparison. We show that transmen viewed voice change as critical to transition success compared to other masculine traits. However, T therapy may not be sufficient to fully masculinize speech: while f o and f o -SD were largely indistinguishable from cismen, VTL was intermediate between cismen and ciswomen. f o was correlated with salivary T, and VTL associated with T therapy duration. This argues for additional approaches, such as behavior therapy and/or longer duration of hormone therapy, to improve speech transition.
... Pubertesini tamamlamış bireylerde doz artırımı daha hızlı yapılabilmektedir (16). İlk 6 ayda cilt yağlanmasında artış, akne, yağ dağılımında değişiklik, vajinal atrofi ve klitoriste büyüme gibi fiziksel değişiklikler görülür, sonraki 6 ayda ise yüz ve vücut tüylerinde artış, kas kitlesinde artış ve seste kalınlaşma gözlenir (22)(23)(24)(25)(26)(27). Hedef serum testosteron düzeyi 400-700 ng/dL'dir, ilk yıl 3 ayda bir sonraki yıllarda yılda 1 veya 2 kez ölçülmelidir (16). ...
... 6 The most likely reason for this is thought to be the effectiveness of hormone therapy in obtaining an acceptable masculine voice. 6 Indeed, f0-related outcomes of long-term androgen treatment of some of the studies that in this field have been summarized in Table 4. [19][20][21][22][23][24][25][26] Including our study, almost all reported an average f0 within cisgender male normative range. However, the details of these studies reveal that this is not the case for each and every individual and several cases can still have an f0 within a gender ambiguous range. ...
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Objective: The aim of this study was to evaluate voice-related outcomes of long-term androgen treatment in trans male individuals.Methods: Trans male individuals who were under hormone treatment for at least one year were evaluated. Self-Perception of Voice Masculinity (SPVM) scale, adapted Transsexual Voice Questionnaire for trans males (a-TVQFtM), Voice-related Quality of Life (V-RQOL), and the mean fundamental frequency (f0) were used to assess voice outcomes. Results: Of the thirteen trans male individuals in this study, the mean age was 26.15 years. The median SPVM was 4, which equated to “somewhat male”. The median f0 was 119 Hz and did not differ from Turkish cisgender male normative data. The median a-TVQFtM scores showed a decreasing trend and the median V-RQOL scale scores showed an increasing trend in accordance with the decrease of median f0 scores. Two individuals were within a gender ambiguous f0 range and a failure rate of 15.4% was observed. Of these two individuals who were still within a gender ambiguous f0 range, one perceived his voice as gender neutral, while the other one perceived his voice as very male.Conclusion: Cross-sex hormone treatment was largely effective in voice masculinization for trans male individuals seeking treatment. Its pitch lowering effect is associated with a significant improvement in the voice-related quality of life of trans individuals, especially in vocal identity. In some cases, a cisgender male frequency may not be achieved. This situation should be evaluated with caution when discussing treatment outcomes and the necessity of additional interventions.
... This is in accordance with studies in adults that measured the largest drop of speaking fundamental frequency within the first 3 months of testosterone treatment. 20,21 Acne was a common side effect and most prevalent at 6 to 12 months of testosterone use. Previous studies among adolescents and adults found that the prevalence and severity of acne were greatest at 6 months of treatment and had decreased at 12 months. ...
Introduction Current treatment guidelines for adolescents with gender dysphoria recommend therapy with gonadotropin-releasing hormone agonists (GnRHa) and testosterone in transgender males. However, most evidence on the safety and efficacy of testosterone is based on studies in adults. Aim This study aimed to investigate the efficacy and safety of testosterone treatment in transgender adolescents. Methods The study included 62 adolescents diagnosed with gender dysphoria who had started GnRHa treatment and had subsequently received testosterone treatment for more than 6 months. Main Outcome Measure Virilization, anthropometry, laboratory parameters, and bone mineral density (BMD) were analyzed. Results Adolescents were treated with testosterone for a median duration of 12 months. Voice deepening began within 3 months in 85% of adolescents. Increased hair growth was first reported on the extremities, followed by an increase of facial hair. Acne was most prevalent between 6 and 12 months of testosterone therapy. Most adolescents had already completed linear growth; body mass index and systolic blood pressure increased but diastolic blood pressure did not change. High-density lipoprotein (HDL) cholesterol and sex hormone binding globulin significantly decreased, but hematocrit, hemoglobin, prolactin, androstenedione, and dehydroepiandrosterone sulfate significantly increased, although not all changes were clinically significant. Other lipids and HbA1c did not change. Vitamin D deficiency was seen in 32–54% throughout treatment. BMD z-scores after 12 to 24 months of testosterone treatment remained below z-scores before the start of GnRHa treatment. Clinical Implications Adolescents need to be counseled about side effects with potential longer term implications such as increased hematocrit and decreased HDL cholesterol and decreased BMD z-scores. They should be advised on diet, including adequate calcium and vitamin D intake; physical exercise; and the use of tobacco and alcohol to avoid additional risk factors for cardiovascular disease and osteoporosis. Strengths & Limitations Strengths are the standardized treatment regimen and extensive set of safety parameters investigated. Limitations are the limited duration of follow-up and lack of a control group so some of the observed changes may be due to normal maturation rather than to treatment. Conclusion Testosterone effectively induced virilization beginning within 3 months in the majority of adolescents. Acne was a common side effect, but no short-term safety issues were observed. The increased hematocrit, decreased HDL cholesterol, and decreased BMD z-scores are in line with previous studies. Further follow-up studies will need to establish if the observed changes result in adverse outcomes in the long term. Stoffers IE, de Vries MC, Hannema SE. Physical Changes, Laboratory Parameters, and Bone Mineral Density During Testosterone Treatment in Adolescents with Gender Dysphoria. J Sex Med 2019;16:1459–1468.
Purpose The goal of this study was to use speech resynthesis to investigate the effects of changes to individual acoustic features on speech-based gender perception of transmasculine voice samples following the onset of hormone replacement therapy (HRT) with exogenous testosterone. We hypothesized that mean fundamental frequency ( f o ) would have the largest effect on gender perception of any single acoustic feature. Method Mean f o , f o contour, and formant frequencies were calculated for three pairs of transmasculine speech samples before and after HRT onset. Sixteen speech samples with unique combinations of these acoustic features from each pair of speech samples were resynthesized. Twenty young adult listeners evaluated each synthesized speech sample for gender perception and synthetic quality. Two analyses of variance were used to investigate the effects of acoustic features on gender perception and synthetic quality. Results Of the three acoustic features, mean f o was the only single feature that had a statistically significant effect on gender perception. Differences between the speech samples before and after HRT onset that were not captured by changes in f o and formant frequencies also had a statistically significant effect on gender perception. Conclusion In these transmasculine voice samples, mean f o was the most important acoustic feature for voice masculinization as a result of HRT; future investigations in a larger number of transmasculine speakers and on the effects of behavioral therapy-based changes in concert with HRT is warranted.
Objectives To identify the most eagerly anticipated change resulting from hormone therapy using gender‐affirming hormones for patients with gender incongruence undergoing a clinical trial. Methods Patients diagnosed with gender identity disorders based on the International Classification of Diseases 10th revision classification at three institutions in Japan for whom hormone therapy using gender‐affirming hormones was initiated were analyzed. They were asked what the most anticipated change was due to gender‐affirming hormone that they had thought of between giving informed consent and the first administration of the drug. Results The responders were 336 transgender men who were administered androgens and 48 transgender women who received estrogens. The median age at commencement of hormone therapy was 24 years for transgender men and 28 years for transgender women. For transgender men, the most frequent answer was cessation of menses (52.7%) followed by a deepened voice (32.4%). For transgender women, breast development (35.4%) was the most anticipated change, followed by gynoid fat deposition (29.2%). Conclusions Cessation of menses in transgender men and breast development/gynoid fat deposition in transgender women might represent primary end‐points in clinical trials evaluating the efficacy of hormonal treatment in these patients.
The chapter reflects the main clinical manifestations of voice disorders, the wide diversity and multiple sociocultural interrelations of which contrast with a consistent systematic order of aetiological or symptomatic categories. Instead, the compilation follows prevailing purposes to provide a useful overview for application in everyday practice. Functional dysphonias, psychosomatic voice dysfunction and singing voice disorders are closely related to each other but nevertheless require individual consideration regarding special diagnostic procedures as well as therapeutic or rehabilitative consequences, including occupational perspectives. Organic manifestations comprise benign lesions of the mucosa of the vocal folds, gastro-oesophageal reflux influences, central and peripheral neurogenic disorders and laryngeal sensory neuropathy. A section on hormone-related dysphonias is followed by a survey on gender vocology focused on the demands of male-to-female as well as female-to-male adaptation of transsexuals. Voice disorders in systematic diseases and also as consequences of environmental influences and allergy complete the chapter that includes paying attention to special aspects of the voices in childhood and adolescence and the elderly population. Malign lesions are not part of this chapter.
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This paper presents a systematic comparison of various measures of f0 range in female speakers of English and German. F0 range was analyzed along two dimensions, level (i.e., overall f0 height) and span (extent of f0 modulation within a given speech sample). These were examined using two types of measures, one based on "long-term distributional" (LTD) methods, and the other based on specific landmarks in speech that are linguistic in nature ("linguistic" measures). The various methods were used to identify whether and on what basis or bases speakers of these two languages differ in f0 range. Findings yielded significant cross-language differences in both dimensions of f0 range, but effect sizes were found to be larger for span than for level, and for linguistic than for LTD measures. The linguistic measures also uncovered some differences between the two languages in how f0 range varies through an intonation contour. This helps shed light on the relation between intonational structure and f0 range.
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The vocal quality of a patient is modeled by means of a Dysphonia Severity Index (DSI), which is designed to establish an objective and quantitative correlate of the perceived vocal quality. The DSI is based on the weighted combination of the following selected set of voice measurements: highest frequency (Fo-High in Hz), lowest intensity (I-Low in dB), maximum phonation time (MPT in s) and jitter (%). The DSI is derived from a multivariate analysis of 387 subjects with the goal to describe, purely based on objective measures, the perceived voice quality. It is constructed as DSI = 0.13 * MPT + 0.0053 * Fo-High – 0.26* I-Low – 1.18 * Jitter (%) + 12.4. The DSI for perceptually normal voices equals +5 and for severely dysphonic voices –5. The more negative the patient’s index is, the worse is his or her vocal quality. As such, the DSI is especially useful to evaluate therapeutic evolution of dysphonic patients. Additionally, there is a high correlation between the DSI and the Voice Handicap Index score.
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The Standards of Care (SOC) for the Health of Transsexual, Transgender, and Gender Nonconforming People is a publication of the World Professional Association for Transgender Health (WPATH). The overall goal of the SOC is to provide clinical guidance for health professionals to assist transsexual, transgender, and gender nonconforming people with safe and effective pathways to achieving lasting personal comfort with their gendered selves, in order to maximize their overall health, psychological well-being, and self-fulfillment. This assistance may include primary care, gynecologic and urologic care, reproductive options, voice and communication therapy, mental health services (e.g., assessment, counseling, psychotherapy), and hormonal and surgical treatments. The SOC are based on the best available science and expert professional consensus. Because most of the research and experience in this field comes from a North American and Western European perspective, adaptations of the SOC to other parts of the world are necessary. The SOC articulate standards of care while acknowledging the role of making informed choices and the value of harm reduction approaches. In addition, this version of the SOC recognizes that treatment for gender dysphoria i.e., discomfort or distress that is caused by a discrepancy between persons gender identity and that persons sex assigned at birth (and the associated gender role and/or primary and secondary sex characteristics) has become more individualized. Some individuals who present for care will have made significant self-directed progress towards gender role changes or other resolutions regarding their gender identity or gender dysphoria. Other individuals will require more intensive services. Health professionals can use the SOC to help patients consider the full range of health services open to them, in accordance with their clinical needs and goals for gender expression.
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The proposal of this basic protocol is an attempt to reach better agreement and uniformity concerning the methodology for functional assessment of pathologic voices. The purpose is to allow relevant comparisons with the literature when presenting / publishing the results of voice treatment, e.g. a phonosurgical technique, or a new / improved instrument or procedure for investigating the pathological voice. Meta-analyses of the results of voice treatments are generally limited and may even be impossible owing to the major diversity in the ways functional outcomes are assessed. A multidimensional set of minimal basic measurements suitable for all “common” dysphonias is proposed. It includes five different approaches: perception (grade, roughness, breathiness), videostroboscopy (closure, regularity, mucosal wave and symmetry), acoustics (jitter, shimmer, Fo-range and softest intensity), aerodynamics (phonation quotient), and subjective rating by the patient. The protocol is elaborated on the basis of an exhaustive review of the literature, of the experience of the Committee members, and of plenary discussions within the European Laryngological Society. Instrumentation is kept to a minimum, but it is considered essential for professionals performing phonosurgery.
This study investigates differences between the self-assessment and external rating of a person's voice with regard to sex characteristics, age, and attractiveness of the voice and mean fundamental frequency (F0). Cross-sectional study. A group of 47 participants with a balanced sex distribution was recruited and the following data were collected: videostroboscopy, voice range profile, F0, self-assessment questionnaire (attractiveness, masculinity or femininity of voice, and appearance), Voice Handicap Index, and questionnaires to determine levels of depression and quality of life. External rating was performed by four experts and four laymen. In both sexes, fair to moderate significant correlations between the self-assessment of masculinity (men)/femininity (women) of voice and masculinity/femininity of appearance could be found, but not between the self-assessment of attractiveness of voice and appearance. In men, a statistically significant correlation was found between external ratings and self-assessment of attractiveness and, with the exception of the female rating group, of masculinity. In women, self-assessment of femininity and attractiveness of voice did not correlate to a statistically significant extent with the evaluation of the external rater. Additionally, the statistical correlation between estimated and real ages was high. Although the objective parameters of age and gender identification could be rated with a high degree of accuracy, subjective parameters showed significant differences between self-assessment and external rating, in particular in rating women's voices. Taking these findings into account in treatments for modifying voice could impede successful interventions. As one consequence, we recommend summarizing target agreements in detail before the treatment.
Objectives/Hypothesis: The aim of the present study was to 1) document voice in a large sample of female-to-male transsexual persons (FMT), 2) compare their vocal characteristics with those of heterosexual biological males, and 3) determine hormonal factors with impact on their fundamental frequency. Study Design: This was a controlled cross-sectional study. It is the largest study to date on voice and voice change in FMT, and the first to include a control group and FMT who were under long-term androgen administration. Methods: Thirty-eight FMT, ranging in age between 22 and 54 years, and 38 controls, frequency matched by age and smoking behavior, underwent a voice assessment that comprised the determination of pitch, intonation, and perturbation parameters measured during sustained vowel production, counting, and reading. Hormonal factors explored were hematocrit, total testosterone level, luteinizing hormone level, and biallelic mean length of the cytosine-adenine-guanine (CAG) trinucleotide repeat sequence in the androgen receptor gene. Results: It was found that the FMT as a group did not differ significantly from controls for any of the acoustic voice variables studied. However, in about 10% pitch lowering was not totally unproblematic. The lowest-pitched (i.e., more male) voices were observed in FMT with higher hematocrit and longer CAG repeats. Conclusion: After long-term androgen therapy, FMT generally demonstrate an acceptable male voice. Pitch-lowering difficulties can be expected in about 10% of cases and appear, at least in part, to be associated with diminished androgen sensitivity.