Tamoxifen refers to tamoxifen citrate tablets, as it will inhibit the growth of estrogen in the patient’s body, which will cause the patient to cause endometrial thickening over a long period of time. Tamoxifen citrate is an antitumor drug mainly used to treat recurrent metastatic breast cancer in women, and can also be used as an adjuvant treatment after breast cancer surgery and to prevent recurrence. Since this drug can inhibit the growth of estrogen in the patient’s body, prolonged use of this drug can lead to thickening of the uterine lining in women. Taking Tamoxifen Citrate Tablets will not only cause thickening of the uterine lining, but will also cause menstrual disorders, amenorrhea, endometrial polyps and even endometrial cancer and other adverse reactions. In addition, it should be noted that it is contraindicated for women with fundus disorders, pregnant women, breastfeeding, as well as during pregnancy. If the endometrial thickness is too serious, it is recommended to go to the hospital in time for examination and treatment according to the doctor’s instructions.