Transvaginal ultrasound is a method of imaging the genital tract in women. The ultrasound machine sends out high-frequency sound waves, which bounce off body structures to create a picture. With the transvaginal technique, the ultrasound transducer (a hand-held probe) is inserted directly into the vagina . It is therefore closer to pelvic structures than with the conventional transabdominal technique (probe on skin of the abdomen), providing superior image quality. This test can be used during pregnancy.