Endometrial thickening does not necessarily lead to cancer. If the thickening is caused by atypical endometrial hyperplasia, the patient may become cancerous in about 3-6 months without treatment. Most patients with endometrial cancer have very thick endometrium, but endometrial thickening does not always lead to cancer, which is related to the cause of endometrial hyperplasia, whether the patient receives timely treatment and how effective the treatment is. For benign endometrial hyperplasia, such as endocrine disorder endometrial hyperplasia, it can be cured by medication. For malignant endometrial hyperplasia, such as atypical hyperplasia, patients mainly show abnormal uterine bleeding. If the endometrium grows excessively and is not treated in time, cancer may occur in about 3-6 months, depending on the pathological results. Women with endometrial thickening are advised to go to the obstetrics and gynecology department of a regular hospital as early as possible to clarify the cause and receive treatment, to have regular follow-up examinations, and to maintain a calm state of mind and regular lifestyle.