Pelvic inflammatory disease, or PID for short, is a group of infectious diseases of the upper female reproductive tract, including endometritis, tubal inflammation, tubo-ovarian abscess, and pelvic peritonitis. If pelvic inflammatory diseases are not diagnosed and treated correctly and in a timely manner, or if the treatment is incomplete, sequelae of pelvic inflammatory diseases may occur, which used to be called chronic pelvic inflammatory disease. The main pathological changes of chronic pelvic inflammatory disease are tissue destruction, extensive adhesions, hyperplasia and scar formation. The clinical manifestations are infertility, ectopic pregnancy, chronic pelvic pain, and recurrent pelvic inflammatory disease. Infertility: tubal adhesions and obstruction can lead to infertility, and the incidence of infertility after pelvic inflammatory disease is 20-30%. 2, ectopic pregnancy: the incidence of ectopic pregnancy after pelvic inflammatory disease is 8-10 times higher than that of normal women, and tubal pregnancy is common. 3, chronic pelvic pain: the formation of adhesions, scarring and pelvic congestion from inflammation often cause lower abdominal cramps, pain and lumbosacral aches and pains, often intensifying after exertion, sexual intercourse and before and after menstruation. The literature reports that about 20% of acute pelvic inflammatory disease episodes are followed by chronic pelvic pain, which often occurs 4-8 weeks after the acute onset of pelvic inflammatory disease. 4. Recurrent pelvic inflammatory disease: Due to the structural damage of the fallopian tubes caused by pelvic inflammatory disease, the local defense function is diminished, and if the patient is still under the same high-risk factors, it can cause re-infection resulting in recurrent pelvic inflammatory disease. About 25% of patients with a history of pelvic inflammatory disease will have another episode. Gynecologic examination (double or triple diagnosis) in patients with chronic pelvic inflammatory disease may show thickening of the fallopian tubes in the form of cords with mild tenderness (tubal lesions), cystic masses with limited mobility (hydrosalpinx or ovarian cysts), retroflexion of the uterus with limited or fixed mobility, thickened and hardened ligaments with tenderness (connective tissue lesions).