Ultrasonographic visualization of the uterus, fallopian tubes, endometrium, and, in pregnant patients, the fetus. The test may be used to diagnose ectopic pregnancy, determine multiple pregnancies, identify ovarian cysts and pelvic cancers, and visualize tubo-ovarian abscesses. To obtain the needed images, the transducer (ultrasound probe) can be placed either on the abdominal wall or within the vagina.