Figure 14. Obstructing leiomyoma in a 27-year-old woman with an elevated level of ß-human chorionic gonadotropin and uncertain gestational dates. US did not allow adequate visualization of the uterine contents or pelvic structures. Sagittal T2-weighted image shows a large leiomyoma in the lower uterus (arrow). The tumor occupies most of the pelvis, creating a potential impediment to delivery.