The following are possible causes of urinary routine occult blood 3+ in women: 1. Infection of the urinary tract. If bacterial invasion of the urethra occurs and an infection is formed, it can cause the epithelium of the urinary tract to become congested and blood to enter the urine, which can be manifested as positive occult blood. It is recommended to retain urine for routine urine examination and urine culture examination to further confirm the diagnosis of urinary tract infection. If the urine routine except urine occult blood 3+, there are also a large number of white blood cells, the number of bacteria significantly elevated, etc., can be diagnosed as caused by urinary tract infection. 2, urinary tract stones. When suffering from urinary tract stones, the stones stimulate the mucous membrane and produce local bleeding, which can cause positive occult blood. It is usually accompanied by pain in the lower back and abdomen, and needs to be further identified by ultrasound of the urinary system.3. If a woman checks her urine routine during her physiological period, that is, during her menstruation, it is possible that vaginal bleeding is mixed in the urine, causing a positive occult blood. Therefore, it is necessary to exclude the presence of a specimen of urine taken during menstruation and resulting in specimen contamination and positive occult blood.