Pelvic inflammatory disease (PID) is usually a mixed infection of endogenous and exogenous pathogens, probably exogenous Chlamydia or Neisseria gonorrhoeae infection causing tubal damage easily followed by endogenous aerobic anaerobic bacterial infection. Common high-risk factors can be divided into the following aspects, and a full understanding of it is beneficial to the correct diagnosis and prevention of PID. 1, Age: Young women aged 15-25 are more likely to get pelvic inflammatory disease, associated with frequent sexual intercourse, ectopic cervical columnar epithelium and poor mechanical defense of cervical mucus. 2. Sexual life: a young age for first intercourse, multiple sexual partners, too frequent intercourse or sexual partners who themselves have sexually transmitted diseases can lead to an increased chance of developing pelvic inflammatory diseases. 3, lower genital tract infections: cervicitis caused by gonococcus and chlamydia, as well as bacterial vaginosis, are closely related to pelvic inflammatory disease. 4. After hysterectomy: hysterectomy such as abortion, hysteroscopy or surgery, and tubal angiography increase the chance of pelvic infection. Multiple surgeries, choosing an irregular hospital to perform the surgery, not paying attention to infection prevention and vulvovaginal hygiene after the surgery, the possibility of pelvic inflammatory disease will be greater. 5, intrauterine device has tail filament ring can be due to vaginitis, cervicitis, untimely treatment, resulting in upstream infection, causing pelvic inflammatory disease 6, poor sexual hygiene: menstrual intercourse, the use of unclean sanitary pads, etc. Low-income groups do not pay attention to sexual health care, vaginal douche people have a high incidence. 7, spread of inflammation: If you have had appendicitis, peritonitis, inflammation may spread to the pelvis, this inflammation is dominated by Escherichia coli infection. 8. Low immune function, overwork, stress and smoking are also associated with the occurrence of pelvic inflammatory diseases.