Whether or not you need to perform urine-holding to check the location of the ring depends on the way the ultrasound is checked. If you need to drink water and hold your urine for an abdominal ultrasound, you can take 500-1500ml of water orally about an hour and a half before the examination and then hold your urine, so that you may be able to hold your urine successfully and have a smoother examination by the time of the examination. If you need to perform ultrasound examination of the vagina, you do not need to hold urine, you can empty the urine in the bladder before the examination, which will help the examination to be more clear, so, it will not have an impact. Checking the position of the ring, both ways can be checked clearly, both can determine the position of the ring, there will not be any error, you can choose according to their own situation at the time of examination.