0,55% of the Danish population are gender incongruent and 0,10% defines themselves as trans gender. These are equally distributed as trans men and trans women. Some of these need gender affirming hormone therapy and gender affirming surgery (GAS). In Denmark, the requirements for surgery are a BMI<27 and BMI<35 for hormone therapy (Frisch et al., 2019). Endogenous sex steroids such as testosterone and estradiol play important roles in the accumulation and distribution of body fat and lean body mass and thus in the feminization and masculinization of body composition (Wells, 2007).~Although the World Professional Association for Transgender Health (WPATH) guidelines for gender affirming surgery (GAS) doesn't specify a BMI requirement (Coleman et al., 2012), as mentioned, in Denmark a BMI<27 is required. Such criteria serve as barriers to essential surgeries and do not have an empirical basis (Brownstone et al., 2021; Martinson et al., 2020). BMI has been widely criticized as a marker of health or wellness due to its two-dimensional nature. Trans gender persons tend to exhibit higher BMI for a range of reasons, including engagement in gender-affirming hormone treatment, higher risk of binge eating and related disorders (Diemer et al., 2015). It is commonly recognized that for those who wish to pursue medical transition, GAS improves health and quality of life (Nobili et al., 2018).~Body fat percentage, measured by BIA, can accurately reflect body adiposity, and serves as a better indicator for obesity (Kyle et al., 2004). Obesity, measured by body fat percentage, is significantly associated with increased surgical complication rate and may be a better indicator for obesity and predictor for postoperative complications than traditionally used BMI (Chun et al., 2013).~Therefore, as fat percentage in trans gender males are relevant to their treatment and alternatively gender affirmation surgery, including mastectomy, the precision of the estimation of body fat percentage using BIA may have real world impact. As seen in the studies above, researchers rely more and more on these estimates in their research and in the clinic.~Hypotheses:~• By optimizing the use of sex specific reference values, we can improve the precision of the estimation of body fat volume using BIA measurements in trans gender males.~Aim:~To assess body composition of trans gender males in hormonal therapy using BIA compared to DXA.~To investigate whether binary reference values using BIA measurements in trans gender males in hormonal therapy is reliable - and thereby if BIA maybe a useful tool for assessing whether a trans gender man is suitable for mastectomy.~This pilot study will be performed as a cross-sectional study.~Following the participants' informed consent, data regarding age, sex, medication, onset of hormonal therapy, and blood samples will be collected from the participants' electronic patient journal. The information gathered is for use in the research project only.~The participants will be measured on the BIA scale twice and once with DXA and they will be asked questions about their habits concerning smoking and exercise. The center for Gender Identity regularly refers trans gender persons to the Department of Health Promotion for weight loss therapy. Patients at the Department of Health Promotion are routinely weighed on the Tanita MC-780 MA-scale. The blood samples collected in this study are routine samples and collected as a part of the participants treatment plan. DXA scans are not standard procedure in this patient group and is the only part of this project which is not part of the patient's regular treatment plan.
0,55% of the Danish population are gender incongruent and 0,10% defines themselves as trans gender. These are equally distributed as trans men and trans women. Some of these need gender affirming hormone therapy and gender affirming surgery. In Denmark, the requirements for surgery are a BMI<27 and BMI<35 for hormone therapy. The hormonal therapy play an important role in the accumulation and distribution of body fat and lean body mass and thus in the feminization and masculinization of body composition.~The BMI requirements for surgery serve as barriers to essential surgeries. It is commonly recognized that for those who wish to pursue medical transition, gender affirming surgery improves health and quality of life.~Body fat percentage, measured by BIA, can accurately reflect body adiposity, and serves as a better indicator for obesity than BMI. Therefore, as fat percentage in trans gender males are relevant to their treatment and alternatively gender affirmation surgery, it is important to have reliable methods for estimating body composition - which is why we wish to compare two different methods for assessing body composition in trans gender males in hormonal therapy.