I'm 5'4" weigh 168 and am just now back in UK14s (so that'd be US 10s I think).
In the past I tended to work on a stone (14lbs) equating to a dress size so 9 stone=10 (I was there once *sigh*) 10st=12, 11st=14, 12st=16 and so on. I think I'm in a smaller size and weighing heavier as I've been really kicking the exercise- both cardio and weights so am about the size I was at 11st7 last time round, if that makes sense

I think alot depends on one's body shape (am lucky to be an hourglass) and also where one shops- I got into a M&S 12 top today but I know I'd probably still be in a 16 at Next.

Interesting thread though, thanks