The specific causes of coffee-colored discharge in women’s vagina are related to the timing of this discharge outflow: 1. The coffee-colored discharge outflow in the middle of two menstrual periods is a normal physiological phenomenon, i.e. ovulatory bleeding. The bleeding is caused by a transient decrease in the estrogen level in the body during ovulation.2. Women with intrauterine device placed in the uterine cavity may experience coffee-colored discharge from the vagina, which is related to the inflammatory reaction of the endometrium caused by the stimulation of the device and can be treated with appropriate medication to stop bleeding.3. Coffee-colored discharge that is not related to the menstrual cycle and is accompanied by itching and odor is caused by gynecological inflammatory diseases such as endometritis and cervicitis.