The abdominal pain and lumbago after intercourse may be related to ovulation, menstrual flow, pelvic inflammatory disease, etc. The causes need to be clarified according to the specific situation and accompanying symptoms, and then medication, etc. 1. ovulation: If ovulation happens after intercourse, some women will experience ovulation pain, which is manifested as mild abdominal pain or lumbago. It usually disappears within one day without treatment. 2. Menstruation: Because of the change of hormone level, some women will have small abdominal pain and lumbago before menstruation, during which intercourse will aggravate the discomfort. The pain is usually persistent and can be accompanied by lumbago and fever. The main treatment is through antibiotics, daily rest and drinking more water; 4. Other: diseases such as tubal inflammation, endometritis or ovarian cysts can cause varying degrees of abdominal pain and lumbago, which may increase after activity or sexual intercourse. It is recommended to seek medical attention and give anti-inflammatory medication, supplemented by surgical treatment if necessary. Pay attention to sexual hygiene before and after intercourse to prevent infection. If there is persistent abdominal pain, lumbago and other uncomfortable symptoms, you should seek medical attention promptly to clarify the cause and treat the cause.