Do you inform your bosses or people covering you when you are pregnant less than 12 weeks?

I have been thinking of this lately. Just wanna hear you guys advice on this.. At least can ease my heart abit. Been feeling abit lost on this. Do you guys think I should tell my boss and my coverer that I am pregger? I am just 5 weeks. So kinda superstitious but don’t know what’s the best.