As is the case with so many illnesses, "an ounce of prevention is worth a pound of cure," because once you've had PID, it can recur, especially if you're a younger woman. In fact, roughly one of every four women with PID will suffer future episodes, and women who are hospitalized for PID have an even greater chance of entering the hospital again with PID or some related condition.

Perhaps even more alarming, recent studies suggest that silent or symptomless PID may be even more common than the classic kind in which acute abdominal pain warns you that something is wrong. However, there is also good news of sorts. Experts believe that symptomless PID is sexually transmitted, probably through germs such as chlamydia and others called trichomonas and mycoplasma. This means that you can avoid PID by sticking with a single partner, using protection, or refraining from sex.