Should i wait to get pregnant?

So here's my situation, I am currently going through La County Sheriff's long process of being hired. My plans even before I applied for the dept was to get pregnant at the end of summer, but now i'm concerned that if I do the dept will hold it against me and find some reason why not to hire me. What do you think, should I wait till after my background investigation to get pregnant, despite the fact that it could take up to a year according to the nurses that I interviewed with. Your opinion would be greatly appreciated