spreading the news...

So before I knew I was pregnant I was at my boyfriend's mother's house. I was feeling pretty nauseous the whole time so she was asking me if I could be pregnant. I just said I don't know, maybe but I don't think so.  Well at thanksgiving EVERYONE, even people I didn't know, was coming up to me saying "do you have any big news for us?!" It put me in such an awkward position. Now that I know I am pregnant, I want to wait a good while before I tell her for sure so that the rest of the world doesn't find out right away either. When did you ladies tell everyone? What week marks the safe spot, when you reach that week your chance of miscarriage gets cut very low?