how soon is it too soon?

Ivonne • Expecting my second child, due July 2017. Couldn`t be anymore blessed or happier then ever! 👨‍👩‍👦‍👦
So I'm barely only 4 weeks pregnant, haven't seen my ob until next week. But I want to know how soon is it too soon to tell the family our news? I don't want to tell anyone just yet at least not until I see my doctor. But once I do when is the right time to let everyone know?