A mammogram is a low-dose x-ray of the breast tissue. You will need to take off your top for the mammogram.
The radiographer will position you so your chest is against the x-ray machine. Your breast tissue is then firmly compressed with a flat, clear, plastic plate. This keeps the breast tissue still and helps get a clear picture. You may find this uncomfortable or painful for a short time. You will need to stay still for a few seconds while the picture is taken.