With me they did not have me empty my bladder. They needed the blatter completely full for a couple reasons one to hold the bladder in a certain position and in doing so the uterus is held into the rught position for taking the pictures. another reason they did inflate the blatter is so that the bladder is not mistaken for the uterus, on the ultrasounds I had both the uterus and the blatter just appeared as a gray black balloon with a hollow middle.