A mammogram is a plain x-ray of your breast. It is the most common way to image the breast and is the chosen modality of imaging in the National Breast Screening Programme. The test involves placing your breast between an x-ray plate and a clear plastic plate which then gently compresses the breast tissue to take an image. Due to the density of breast tissue, this test is not regularly undertaken under 40 years of age. Sometimes extra views are required, but usually only 2 images are taken per breast. Occasionally other tests are indicated such as needle biopsy.