Risk of pelvic inflammatory disease among intrauterine-device users irrespective of previous pregnancy.

The use of intrauterine devices (IUD) in 690 patients admitted to hospital for pelvic inflammatory disease (PID or acute salpingitis) was compared with the use in a sexually active age-matched control group. 220 (31.9%) of the patients and 114 (16.5%) of the controls were using an IUD. Thus, the risk of PID was raised twofold by IUD use. No significant difference was found between the women who had never been pregnant and those who had in the two groups. Neither was the risk of PID found to vary with age.