Introduction: Mammographic density, as well as the risk of developing breast cancer, is related to multiple risk factors such as age, genetic and hereditary factors, obesity, diet, smoking, alcohol consumption, and in some studies, an association has been observed with a less common factor, which is the length of fingers or the digit ratio, specifically focusing on the measurement of the second and fourth fingers (2D:4D). Materials and Methods: Trasversal study. The population of this study consists of women attending screening mammography at Clínica Colombia (Colsanitas) in the city of Bogotá between 2019 and 2022. The relationship between mammographic density and the ratio of the length of the second and fourth fingers of the left hand (D2:D4) is evaluated using linear regression, with the logarithmically transformed mammographic density as the dependent variable. The model is adjusted for age, body mass index, parity, family history of breast cancer, age at menarche, menopausal status, and parity. Results: In the present study, we did not find a relationship between mammographic density and D2:D4. This could be due to the absence of a real association between in-utero testosterone exposure and breast cancer or that such an association is not mediated by mammographic density.
