Men who have CT examination has some effect on the preparation for pregnancy, it is recommended to have normal fertility after 3 months. X-ray irradiation in CT examination can cause testicular spermatogenic epithelial dysfunction, spermatogenic epithelial atrophy, decreased sperm count, decreased motility, and increased sperm deformity. It is generally not recommended to prepare for pregnancy during the time within 3 months of the CT examination. This is because it takes about 3 months for the testicular spermatogenic cells to produce a new batch of spermatozoa after producing spermatozoa, and it is only at this time that the old spermatozoa may be metabolized by the organism. Therefore, in order to avoid problems such as fetal malformation, it is recommended that it is more appropriate to prepare for pregnancy after 3 months. To summarize, given that it takes about three months for a man’s sperm to be completely renewed, from the perspective of eugenics, it is best to consider preparing for pregnancy after three months after the ct test.