Introduction: Mammographic breast density is a measure of parenchymal breast patterns on film and in part a marker of cumulative exposure to oestrogen. The risk of breast cancer for women with increased density is up to six fold more than in women with less dense tissues. The pattern of mammographic breast density among Ugandan women is not known. Objective: To establish these as a contribution to baseline data. Methods: A cross sectional descriptive study that enrolled women presenting for mammography at the national referral hospital radiology department. Breast densities were scored using the BI-RADS categories. IRB approval was obtained. Results: Of the 190 women enrolled, 178 were scored, of those scored 10 (5.3%) had extremely dense breasts (grade IV) and 39 (20.5%) had heteregenous ones (grade III). The rest 129 (67.9%) had scattered fibroglandular or fat densities (Grades I & II). Most of the women were young 45.8 ± 12.5 years The majority had normal or benign mammographic findings and all were non pregnant. Conclusion: Mammographic densities in this Ugandan population appear to be of low grade. The pattern established here is markedly different from findings in other studies that indicated much higher proportions for high dense tissues in other races. Mammographic interpretation of films could therefore be easier.

Key words: mammography, breast, density