In recent years, it is not uncommon to encounter such patients in the clinic, with an ultrasound report form and a stack of antibiotic prescriptions in hand, recounting a long history of treatment for pelvic inflammatory disease. Why is this happening? Is it the high incidence of pelvic inflammatory disease? Is it that antibiotics are resistant and ineffective? Or is it a problem with the physician’s consultation. Pelvic inflammatory disease (PID) is a group of diseases caused by inflammation of the upper female reproductive tract, including endometritis, tubal inflammation, tubo-ovarian abscess, and pelvic peritonitis. Because the site of PID is deep in the pelvic cavity, the pathogenic microorganisms are not easy to collect, and the symptoms and signs vary in severity, which makes it difficult to make a clear diagnosis and thus makes it difficult to standardize clinical treatment. There are two main sources of pathogens in PID: 1) endogenous pathogens, which come from the original vaginal flora, including aerobic and anaerobic bacteria, and are commonly found in mixed infections. The main pathogens are Staphylococcus aureus, Streptococcus haemolyticus, Escherichia coli, Bacteroides fragilis, Streptococcus digestiveis, etc. Nearly 80% of pelvic abscesses can be cultured with anaerobic bacteria. 2, exogenous pathogens, mainly the pathogens of sexually transmitted diseases, such as chlamydia, gonorrhea bacillus and mycoplasma, others are tuberculosis bacillus, rare are pseudomonas aeruginosa. So under what circumstances do women develop pelvic effusion? Under normal physiological condition, there will be a small amount of exudate from internal organs, blood vessels and lymph in the abdominal cavity, about 200ml, whose main function is to lubricate the organs. After ovulation, the follicular fluid flows out due to the rupture of the follicles, which also becomes part of the “pelvic fluid”, because the pelvic cavity is located in the deepest part of the abdominal cavity, so there will be fluid accumulation in the female pelvis. At this time, the ultrasound will “see” a “pelvic fluid” of 0~3.8cm. Generally, pelvic fluid less than 3cm without any clinical manifestations is considered physiological fluid, so pelvic inflammatory disease cannot be diagnosed based on “pelvic fluid”, and such pelvic fluid does not require treatment. However, some clinics or hospitals and other medical institutions currently give a lot of antibiotic treatment based on the return of pelvic fluid from ultrasound, gynecological examination of the uterus or a part of the adnexal area with pressure pain, and then the doctor says that the area is “thickened” and diagnosed as chronic pelvic inflammatory disease, which medically increases the chance of drug resistance. Antibiotics play a vital role in the treatment of PID, but it does not mean that the more advanced and expensive antibiotics are used, the better. The proper use of appropriate antibiotics is the key to actively treat PID and reduce side effects. The antibiotics should be used in sufficient quantity, in sufficient course, and in combination with multiple doses, to treat the pathogens according to the drug sensitivity test. The chronic PID general antibiotic treatment is not effective, but when there is a subacute attack, antibiotic treatment should be given. Because bacteria are often resistant to general antibiotics, new broad-spectrum antibiotics should be used.