After holding back the pain in the left lower abdomen, the main consideration is ureteral reflux, ureteral stones, bladder injury, ureteral inflammation, etc. 1, ureteral reflux: normal physiological anatomical structure is the bilateral ureter and the bladder connected to the place of a one-way valve, urine can only flow from the kidney to the ureter to flow to the bladder again. When holding back urine for too long and too much, the one-way valve will be destroyed, and when the one-way valve on the left side is destroyed, the urine in the bladder will flow upwards along the ureteral orifice on the left side into the left renal pelvis, resulting in pain in the lower left side of the abdomen. This condition suggests not to continue to hold urine, as early as possible to relieve urination; 2, ureteral stone: ureteral stone is a common clinical disease, when the stone to the left side of the ureter, especially when the stone sliding in the ureter, easy to cause ureteral smooth muscle spasm, renal colic. It is recommended that patients do abdominal CT scanning to clarify the presence of ureteral stones, and according to the size and location of the stone, as well as whether there is no obstruction, to determine the method of stone removal; 3, bladder injury: long-term urinary retention can lead to the control of bladder contraction of the muscles due to ischemia or over-expansion of the bladder contraction of the strain is impaired, which can lead to the emergence of the left lower abdominal pain after urinating, urinary frequency and other symptoms. Treatment is usually taken symptomatic treatment, such as pain treatment, adequate drainage of urine; 4, ureteral inflammation: bacterial inflammatory lesions in the ureter can lead to frequent urination, urinary urgency, dysuria, lumbar pain, lumbago, pain in the lower left abdomen and other symptoms; 5, adnexitis: women holding urine after the pain in the lower left abdomen may also be caused by adnexitis, often accompanied by increased vaginal discharge and other symptoms. It can be treated with antibiotics under the guidance of a doctor, and commonly used drugs are cefotaxime sodium, cefazoxime, etc.; 6, prostatitis: if the male patient after urination, the pain in the left lower abdomen symptoms can not be relieved, it may be caused by prostatitis.