A life table analysis technique for the evaluation of intrauterine contraceptive devices.

417 patients in a single practice who were fitted with 562 IUDs over a 13-year period were surveyed prospectively. 389 1st time users of 5 principal IUD types were reviewed using a computer-derived life table analysis technique. In parous patients followed over a 10-year period, the Saf-T-Coil 33SX achieved significantly better overall results than any other type of device used. In nulliparous women using the Gravigard, no pregnancies occurred and removal for medical reasons such as infection appeared to be less frequent than in those using the Dalkin N Shield. Overall, this study did not show that device-related events, particularly infection, occurred significantly more often in nulliparous women. The relatively small cohort numbers and other undefined characteristics may account for this variance from other surveys.