Pelvic inflammatory disease (PID) is an acute or chronic inflammation in the pelvic cavity. It is most commonly caused by sexually transmitted diseases, including chlamydia and gonorrhea, that have ascended into the uterus, fallopian tubes, or ovaries as a result of intercourse or childbirth, or of surgical procedures, including insertion of IUDs or abortion. PID may be either symptomatic or asymptomatic. It may cause infertility and it may raise the risk of ectopic pregnancy. PID is a disease associated with HIV infection.