The purpose of holding urine for color ultrasound is to allow the bladder to expand and fill, and the enlarged bladder will push the intestinal tubes to one side, thus reducing the interference of the gas in the intestines on the organs that need to be examined, and making the organs that need to be observed appear more clearly, and the results will be more accurate. In clinical work, urinary system ultrasound, gynecological ultrasound, obstetric examination of women in early pregnancy, as well as cervical canal measurement in late pregnancy need to hold urine. When a pregnant woman’s uterus enlarges to a certain extent, it can also push the distended bowel to one side. Therefore, it is not necessary to hold your urine during an ultrasound in a woman with a larger gestational month. The correct way to hold urine is to drink about 1,000ml of warm water about an hour before the examination, and to exercise properly after drinking the water, which can promote urine formation.