Based on the density of breast tissue in different age groups and the high incidence of breast cancer in Chinese women, the following recommendations are made for the frequency of mammography examinations in different age groups: mammography is generally not recommended for women under 25 years of age; mammography should be done for women aged 25 – 35 years who are clinically suspected of having malignant breast lesions or for women over 35 years of age who are clinically examined for either benign or malignant lesions. A mammogram is recommended for every woman between the ages of 35 and 40 years to provide a baseline for comparison with future mammograms and to help detect changes, usually referred to as a baseline mammogram; mammograms are recommended once every 1.5 – 2 years for women 35 – 40 years and older than 55 years; mammograms are recommended once every 40 – 55 years. Mammograms are recommended once a year for women aged 55 years and once a year for other high-risk groups.