The reason for this symptom is not exactly the same among different individuals.1. Some women will have obvious falling sensation in the lower abdomen before or during menstruation, which is a clinical symptom caused by chronic pelvic inflammatory disease, and this symptom will be relieved or disappeared after menstruation is over; 2. Some women will have obvious falling sensation in the lower abdomen during or after sex, which is usually caused by chronic uterine inflammation or chronic pelvic inflammation; 3. During or after sex, there will be obvious discomfort in the lower abdomen, usually caused by chronic inflammation of the uterus or chronic pelvic inflammatory disease; 3, some women will have a short history of menopause before this symptom, need to be highly suspected of pregnancy symptoms of preeclampsia or ectopic pregnancy, need to do an ultrasound examination to determine.