Colocolic fistula caused by a previously inserted intrauterine device. Case report.

Uterine perforation remains the most serious complication of the intrauterine contraceptive device (IUD). It is more common in the puerperium, usually occurring at the time of insertion of a new device. Perforation may, however, also occur in the puerperium if a pre-existing device is not removed in early pregnancy or extruded at the time of delivery. The case is presented of a 30-year-old woman who became pregnant for the third time following insertion of an IUD in the puerperium of her second pregnancy. An uneventful pregnancy and delivery followed. Failure to detect the IUD at the time of delivery led to laparoscopy and laparotomy to locate the device. A colotomy was necessary to retrieve the device, which had formed a colocolic fistula. It is concluded that the puerperium remains the time of greatest risk of uterine perforation by an IUD. Although most occur at the time of insertion, this complication can also occur with a previously inserted device. Severe intra-abdominal complications may ensue if the device is not localized and removed. Laparotomy is justified if the laparoscopic removal is unsuccessful. A high degree of suspicion is necessary if serious consequences are to be avoided.