If there is sudden pain in the lower abdomen, it is mainly due to the following reasons: 1. Ovarian cyst twisting, when there is an ovarian cyst, due to gravity, it may cause twisting of the tip, it will manifest as sudden pain in the lower abdomen, often accompanied by nausea, vomiting symptoms, it is recommended to go to the hospital for ultrasound examination, basically to confirm the diagnosis, and it is recommended to give timely surgery. 2. Chronic pelvic inflammatory disease Acute attack, when there is chronic pelvic inflammatory disease, the body’s resistance decreases or strain, it may lead to an acute attack, there will be a sudden lower abdominal distension and pain, and accompanied by increased vaginal discharge phenomenon, through gynecological examination, laboratory tests can basically confirm the diagnosis, it is recommended to actively give anti-inflammatory treatment, while doing physical therapy of the lower abdomen to promote the absorption of inflammation.