1st pregnancy we told everyone immediately - miscarried at 9 weeks
Emily - we told my mother and best friend immediately, everyone else at about 10 weeks when we had a scan and everything looked fine
3rd pregnancy - only told my mother because I knew something wasn't right. Miscarried at 6 weeks
Toby - told mum immediately (there's a pattern here LOL), everyone else around 10 weeks because I couldn't hide my belly otherwise I would have waited a few weeks longer.