The best time for mammography is 7-10 days after the menstrual cycle, when breast lesions are easily detected. The female breast is influenced by the endocrine level in the body, and estrogen and progesterone in the body have the greatest impact on the breast. Increased estrogen can cause hyperplasia of the breast ducts, while increased progesterone can cause hyperplasia of the breast follicles, both of which can increase the volume of the breast and make the texture slightly harder. During the 7-10 days after the menstrual cycle, the hormones in the body return to the basal level and have the least effect on the breast. When palpation and imaging of the breast are performed at this time, more lesions can be detected, thus avoiding missed diagnosis and misdiagnosis. For postmenopausal women, the estrogen and progesterone in their bodies are stable and the time for breast examination is not restricted. In daily life, women can perform self-examination of the breast by pressing the breast with their fingers flatly, not grasping and pinching the breast with their fingers, and touching each quadrant of the breast clockwise to clarify the presence of hard nodes and pain, and seeking timely medical attention in case of abnormalities.