Endometrial thickening and left adnexal cysts are common gynecological disorders. Endometrial thickening can be seen in endometrial polyps, endometrial hyperplasia, endometrial cancer, etc.; left adnexal cysts can be seen in chocolate cysts, inflammatory cysts, and physiological cysts. The two diseases can develop at the same time or separately. 1. Endometrial thickening: endometrial thickening can be diagnosed by means of color ultrasound, and hysteroscopy and curettage are needed to further understand the condition. Causes of endometrial thickening include endometrial polyps, endometrial hyperplasia and endometrial cancer. These conditions need to be treated by surgery. 2. Left adnexal cysts: left adnexal cysts include chocolate cysts, inflammatory cysts and physiological cysts, etc. Some of the cysts with small diameters can be absorbed on their own, while some of them with large diameters need to be treated by laparoscopic surgery. There are many reasons for endometrial thickening and left adnexal cysts, especially those with endocrine disorders, which are more likely to occur, and it is recommended to go to a professional gynecological hospital in time for treatment.