Intrauterine devices and pelvic inflammatory disease.

There is convincing clinical evidence that PID is more common in IUD users than in users of other contraceptive methods. There appears to be a smaller but significant increase when IUDs are compared with sexually active noncontraceptive users. However, the incidence of PID severe enough to warrant hospitalization is only of the order of 1 to 2 per 1,000 women per year. The question which remains is whether beyond this low figure of moderate and severe disease there is a much higher incidence of subclinical PID which may result in complications for IUD users. Development of a marker such as C-Reactive protein or the split complement component C3d to detect mild PID would prove invaluable in the elucidation of several crucial problems in the clinical management of women using IUDs.