Proliferative changes in the endometrium are a result of scraping pathology, a process of normal endometrial changes. The endometrium is the layer of the uterine lining that responds to estrogen and progesterone and changes significantly with the menstrual cycle. The cycle of endometrial changes can be divided into 3 phases: the proliferative phase, the secretory phase and the menstrual phase. The proliferative phase of the endometrium usually occurs during the 5-14 days of the menstrual cycle, which corresponds to the development of follicles from the basal follicles to the mature follicles. During this phase, the thickness of the endometrium gradually increases under the influence of estrogen. The proliferative phase of the endometrium can be further divided into early, middle and late phases. The early stage usually refers to days 5-7 of the menstrual cycle, when endometrial proliferation has already started and the lining is thin; the middle stage is mainly characterized by a relatively rapid proliferation of glandular epithelial cells; days 11-14 of the menstrual cycle are the late stage of the proliferative phase, when endometrial thickening is more pronounced and the surface is wavy. In addition to the proliferative phase of the endometrium, the secretory phase of the endometrium can also continue to synthesize and secrete estrogen and progesterone as well, and the endometrium will continue to thicken. Therefore, if the scraping pathology examination indicates thickening of the endometrium during the proliferative or secretory phase, it is mostly a normal physiological phenomenon and no special intervention is needed. However, the presence of abnormal endometrium, such as endometrial hyperplasia or even endometrial cancer, is sometimes reported on scraping pathology and requires active management.