*LOL* I've definitely heard of that happening. We found out at 20wks that Maddy was a girl (the sonographer pointed out the genetalia as bubs was showing it for all to see! *L*) and I was so scared that in following scans that we would be told otherwise. We had names picked out so when we found out baby was a girl, we started referring to her by name. Fortunately both 22wks & 32wks scans confirmed the gender; and then out popped a gorgeous little girl just like we had been promised!

(I can definitely see the argument for not finding out though - I think I would have been devastated had she turned out to be a boy. Not because I don't want a boy (we're hoping for our 'Kian' next time round), but because I had mentally prepared myself for a little daughter)