A spectrum of inflammation involving the female upper genital tract and the supporting tissues. It is usually caused by an ascending infection of organisms from the endocervix. Infection may be confined to the uterus (ENDOMETRITIS), the FALLOPIAN TUBES; (SALPINGITIS); the ovaries (OOPHORITIS), the supporting ligaments (PARAMETRITIS), or may involve several of the above uterine appendages. Such inflammation can lead to functional impairment and infertility.