Pain below the left side of the navel of a woman may be caused by gynecological diseases, urinary system diseases, digestive system diseases and so on. 1. Gynecological diseases: pain below the left side of the female navel may be the left side of the fallopian tube, ovary lesions. Such as left ovarian cysts, ovarian torsion, tubal inflammation, tubal tuberculosis, pelvic inflammatory disease, etc., can cause pain in the left lower abdomen. 2. Urinary system diseases: If accompanied by abnormal urination symptoms, such as increased urination, pain after urination, hematuria and other symptoms, we should consider the urinary system diseases, such as inflammation of the urinary system, stones, inflammation stimulation or stone incarceration, which can cause pain in the left lower abdomen. 3. Digestive system diseases: left lower abdominal pain can also be considered related to digestive system diseases, such as acute and chronic inflammation of the left side of the intestinal tract, tumors and so on. The stimulation of inflammation or gradual growth of tumor can cause left lower abdominal pain. In addition to this, irritable bowel syndrome, ulcerative colitis, intestinal obstruction, are also possible causes of lower left abdominal pain. Women with persistent pain in the lower left abdomen are advised to go to the hospital for timely examination to clarify the cause.