A mammography apparatus has a bed unit on which, during a screening, the patient lies ventrally on a recumbent surface of the bed unit. The recumbent surface has a configuration allowing variable individual parts of the bed unit to be positioned so that the bed position of the patient is optimized and the components of the x-ray unit that are arranged below the bed unit can be positioned and aligned relative to one another such that the base of the breast to be x-rayed is also imaged.