Klaver M, et al. - The clinicians performed this study to determine the effects of body fat and lean body mass in separate body regions and on body shape after 1 year of cross-sex hormonal therapy (CHT). In transwomen, CHT caused a more feminine body fat distribution and a lower waist-to-hip ratio (WHR). On the other hand, it caused more masculine body fat distribution with a lower hip circumference in transmen.

Methods

• The clinicians conducted this multicenter prospective study at university hospitals.
• They included 179 male-to-female gender dysphoric persons, referred to as transwomen, and 162 female-to-male gender dysphoric persons, referred to as transmen.
• For this study, all participants underwent whole body dual-energy X-ray absorptiometry and anthropometric measurements before and after one year of CHT.

Results

• Increases in body fat ranged from +18% (95%CI 13%;23%) in the android region to +42% (95%CI 37%;46%) in the leg region and +34% (95%CI 29%;38%) in the gynoid region among transwomen.
• Changes in body fat ranged from -16% (95%CI -19;-14%) in the leg region and -14% in the gynoid region (95%CI -16%;-12) to no change in the android region (+1%, 95%CI -3%;5%) in transmen.
• Mainly because of an increase in hip circumference (+3.2 cm, 95%CI 2.3;4.0), WHR decreased in transwomen (-0.03, 95%CI -0.04;-0.02).
• Findings revealed that transmen decreased in hip circumference (-1.9 cm, 95%CI -3.1;-0.7).
• This caused an increase in WHR (+0.01, 95%CI 0.00;0.02) in transmen.