Pelvic inflammatory disease
Other things can cause the same infection as PID. This could be a complicated pregnancy, appendicitis, swollen or twisted ovaries, and endometriosis. A woman is more likely to get Pelvic inflammatory disease if she has had it before.  She is more likely to have the infection if she has recently had sex, started menstruation, had an Intrauterine device put inside her uterus or if her sex partner has a sexually transmitted infection.