They say as soon as a heart-beat is detected that the pregnancy is usually viable, so I'd say to tell your close friends and family than is safe. And as for others, I'd rather wait until after week 12 when you're out of the first trimester and you know things are safer.I had a miscarriage my first pregnancy at 9 weeks, and I hadn't told anybody about it yet because I was 19 and it was unplanned... so I found it easier for my fiance and I to just deal with the pain alone. Than with the 2nd pregnancy, we had been trying to conceive, and I waited until we were 12 weeks to tell our family (I was paranoid after the first pregnancy!) and than I didn't tell friends or co-workers until I was 20 weeks and already knew the gender! It was kind of fun keeping a secret that not many people know! :)Now we are on are 3rd pregnancy and I'm 6 weeks and haven't told friends or family yet... but will probably wait until 12 weeks at least...But it's a personal decision, if something were to happen (God Forbid!) and you know that you'd need the support of friends and family to get thru it, than I say tell them as early as you want. :) Congrats & Good Luck w/ your Pregnancy!