Ultrasonography and missed threads of IUDs.

PIP: Ultrasonography was performed in 26 patients with missed IUD threads. It was accurate in 89% of the cases, and IUDs in utero were/easily identified. However, in cases of extrauterine devices, ultrasonography showed only a empty uterine cavity; it failed distinguish between an expelled device and one that had perforated the uterus. In the case of pregnancy on top of the device, ultrasound was the best diagnostic modality for detecting the pregnancy and its duration.^ieng