An ultrasound imaging apparatus is disclosed, comprising a processor configured to obtain an ultrasound image, a display configured to display the ultrasound image, and a controller configured to identify a menstrual cycle based on a state of an endometrial region on the ultrasound image and configured to control the display to display the identified menstrual cycle. The controller may identify the menstrual cycle based on at least one of the brightness and the contrast of the endometrial region, in particular based on at least one of the thickness of the endometrial region, the presence of a line having a high shade, and the number of such lines on the ultrasound image. When the menstrual cycle is identified, the controller may identify whether a diagnostic parameter such as a measured size of the uterus is normal or not, based on a predetermined range corresponding to the identified menstrual cycle.
