People and dogs who have been recently x-rayed are not a danger to others. They don't suddenly start giving off radiation themselves (above background levels).

I've never heard about pregnant women having to avoid people who had a recent x-ray. According to the Mayo Clinic: "The possibility of an X-ray during pregnancy causing harm to a fetus is very small. Generally, the benefits of the information from an X-ray outweigh the risks."

Source: https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/expert-answers/x-ray-during-pregnancy/faq-20058264

I think you might be confusing it with midly radioactive injections. My gf was given one to study how well her lyph nodes function and distribute the liquid. She was tol not to hang around pregnant people too long.