Endometritis occurring during menstruation can result in increased menstrual flow and extended periods. The most common clinical symptoms of endometritis include lower abdominal pain and increased vaginal discharge. The abdominal pain is often persistent and worsens with activity or after intercourse. In severe cases, it may also be accompanied by fever, chills, headache, loss of appetite, and fatigue. If accompanied by peritonitis, symptoms related to the digestive system such as nausea, vomiting, diarrhea, abdominal distension, and diarrhea may occur. If there is an associated urinary tract infection, symptoms can include urinary urgency, frequency, and pain. If symptoms of bladder irritation occur, there may be difficulty in urination and frequent urination, and the bladder muscle may also have pain. If a mass is located behind the uterus, it can cause rectal irritation symptoms, leading to diarrhea, a sense of urgency to defecate, and difficulty in urination.