Fig. 3

a Breast tissue density was assessed by a radiologist using four categories with increasing amounts of fibroglandular tissue (epithelium and fibrous stroma). Mammograms were from transmasculine subjects. b There was no association between the duration of testosterone therapy (TT) and breast tissue density (rho = − 0.09, 95% Confidence Interval (CI) − 0.38, 0.22, p = 0.58)