The radiation dose of an ordinary chest X-ray is 0.02 mSv, which is quite low. If you are a patient preparing for pregnancy, try not to have radiation-based tests. If such tests must be done, such as a chest X-ray, wait at least 3 months before preparing for pregnancy. The radiation dose from a chest X-ray is very low and there is no need to worry too much. There are thresholds for the adverse effects of X-rays on all mammals and young, including humans, and even embryos, and the radiation dose received by either an adult or a fetus must reach a certain level before damage occurs.