X-ray ionizing radiation is damaging to the human body, and the longer the exposure time and the closer the distance, the greater the risk of disease, such as chest X-ray, fluoroscopy or CT, etc. If you are exposed to X-rays for a long time, because the radiation dose can be accumulated in the body, it will destroy a large number of human white blood cells and reduce the number of white blood cells in the human blood, which will lead to a decrease in the body’s immune function and make it easy for pathogenic microorganisms to invade the body and cause diseases, especially fetuses and children are very sensitive to X-rays. Therefore, pregnant women, infants and children should avoid or reduce x-ray examinations as much as possible.