Endometrium 19mm indicates that the endometrium is thicker, it has two reasons, namely physiological and pathological, physiological is not serious, no need to treat; pathological may be related to endocrine disorders, ovarian functional tumors, endometrial carcinoma, etc. Tumors caused by the more serious, generally can be taken medication or surgical treatment. The thickness of endometrium is not constant, during menstrual cycle, the thinnest endometrium is only 2~3mm, and the thickest endometrium can be 2~2.5mm, which is closely related to estrogen level, and the endometrium will be thickened when the level of estrogen is increased, which can be seen in physiological situation, such as before menstruation, long-term oral estrogen preparation, etc. However, these are not serious, and need to be rechecked after menstruation. Pathological endometrial thickening can be seen in endocrine disorders, such as polycystic ovary syndrome, anovulatory dysfunctional uterine bleeding, etc. Due to sparse ovulation or no ovulation, there is only estrogen in the body without progesterone resistance, which will cause the endometrium to proliferate. These diseases are not serious and can be treated with oral progesterone capsules, ethinyl estradiol cyproterone, etc. If necessary, diagnostic scraping can also be taken. In addition, some estrogen-related malignant tumors can cause endometrial thickening, such as endometrial cancer, malignant granulosa cell tumor and follicular membranous cell tumor, etc. These diseases are more serious, with higher recurrence and metastasis rates, which can affect life expectancy. They should be treated with surgery, radiotherapy and other measures according to the stage and type of tumor. The endometrium is 19mm, we suggest to consult doctor in time and follow up the treatment according to doctor’s advice.