Migration of an intrauterine contraceptive device during the course of pregnancy: a case report.

Uterine perforation by a contraceptive intrauterine device (IUD) is a relatively rare event. These events may result secondary to mechanical force applied during placement (primary perforation) or migration by uterine contractions or surgical manipulation after placement (secondary perforation). A 33-year-old woman with an IUD placed 9 years before admission visited the emergency department with an early pregnancy and a 3-day history of vaginal bleeding. Vaginal examination revealed IUD strings visible at the cervical os, and transvaginal ultrasound confirmed the presence of an IUD in the lower uterine segment and upper cervix. The IUD migrated spontaneously to the fundal myometrium at 15 weeks' gestation. Premature rupture of membranes ensued at 20 weeks' gestation, and, at delivery, the IUD could not be retrieved. Subsequent computed tomography confirmed that the IUD was incompletely embedded in the fundal myometrium and partially extending into the peritoneal cavity. At laparoscopic sterilization 6 weeks later, the IUD had perforated the small bowel, and the device was removed with concomitant bowel repair. This case documents spontaneous migration of a copper IUD from the lower uterine segment through the fundus during early pregnancy and supports removal of asymptomatic ectopic IUDs whenever possible.