Mixed mass in the left adnexa may be caused by left ovarian cyst, left inflammatory infection, left ovarian cancer and so on. 1. Left ovarian cyst: endocrine disorders or excessive psychological pressure and poor living habits may lead to cysts in the left ovary, resulting in the formation of mixed masses locally, which may cause abnormal menstrual cycle and other manifestations. 2. Inflammatory infection on the left side: due to long-term chronic inflammatory stimulation in the left adnexal area, it will easily lead to local tissue proliferation and formation of mixed masses, which is often accompanied by symptoms of pain in the left side of the abdomen. 3. Left ovarian cancer: when cancer occurs in the left ovary, mixed masses will appear, and there are no symptoms in the early stage, but with the further development of the disease, patients may have lower abdominal pain, abnormal menstrual cycle and other symptoms. If patients’ examination reveals the presence of mixed mass in left adnexa, it is recommended to go to the hospital in time to find out the cause of the disease and then carry out standardized treatment, so as to avoid delaying the condition.