"An even more reassuring fact is that the risk of radiation- induced breast cancer is lowest among women who received the exposure later in life, as they would with mammography," [Judith Willis] says, explaining that radiation risk is greatest when the exposure occurs in puberty.

Technicians perform the mammography, position the patient, operate the X-ray equipment and develop the film. Radiologists are medical doctors who interpret the mammogram results. These professionals are specially trained to obtain the best possible image with minimal radiation exposure and to properly interpret the X-rays.

Compression of the breast by a device called a "paddle" is necessary for proper positioning. The paddle is about the size of a sheet of notebook paper. With some equipment, the technician uses the paddle to manually compress the breast. The paddle stays in position while the technician goes behind an X-ray shield and takes the X-ray.