Endometrial thickening is manifested during the menstrual cycle when the endometrium is subjected to estrogen and enters the proliferative and secretory phase. As estrogen and progesterone levels drop, the endometrium peels off and vaginal bleeding occurs, which is menstruation. If the menstrual cycle is irregular, excessive thickening of the endometrium is a pathological state, caused by endocrine disorders under the stimulation of estrogen for a long time, or by drug stimulation such as tamoxifen, causing endometrial hyperplastic lesions. Endometrial hyperplasia manifests itself as prolonged menstrual irregularities. Irregular vaginal bleeding or prolonged heavy vaginal bleeding after a period of menopause can be treated by diagnostic scraping, and the scraped out endometrial tissue is sent for pathological examination, and the corresponding treatment plan is decided according to the pathological examination results. The pathological examination results are divided into simple hyperplasia, compound hyperplasia and atypical hyperplasia. Atypical hyperplasia should be taken seriously as there is a possibility of cancer.