Pelvic Inflammatory Disease (PID) is the inflammation or infection of the fallopian tubes or ovaries. In many cases, PID develops when the chlamydial infection spreads into the uterine cavity and extends into the tubes. A woman who has PID will experience low abdominal pain, vaginal discharge and fever. PID can be diagnosed by a pelvic exam. Doctors usually prescribe oral antibiotics, but hospitalization may be required in severe cases.

PID can result in scarring of the fallopian tubes, which can block the tubes and prevent fertilization from taking place. In other cases, scarring may interfere with the passage of the fertilized egg down into the uterus. When this happens, the egg may implant in the fallopian tube. This is called ectopic or tubal pregnancy. This is life-threatening for the mother and results in the loss of the fetus. In severe cases, PID can cause permanent tubal damage and infertility.