IUD--related uterine perforation: an epidemiologic analysis of a rare event using an international dataset.

An international dataset of 21,610 IUD insertions revealed 41 uterine perforations occurring at the time of, or subsequent to, insertion. Dat were collected on standard forms. Perforations were classified as confirmed, probable, or possible, based on the clinician's judgement and subsequent management. The uterine perforation rate was estimated as between 1.9 and 3.6/1000 insertions. 13 of the total 41 perforations were reported from 2 of 72 cooperating clinics. In 1 clinic, this center-clustering phenomenon suggested an effect of a high risk device. In the other clinic, the effect of insertor (operator) inexperience was indicated. A case-control analysis delineated previous cesarean section as a host risk factor (P0.05, McNemar's chi square). Further investigation of this association by similar case-control studies is recommended.