I got this too right through Toby's pregnancy
My OB's was doing u/s measurements right through my pregnancy that consistently said he would be 8lbs and he kept saying he was "big". What cr@p. 8lbs is the 50th percentile which (and I am not a doctor but I'll hazard a guess here ) means that he is average sized.
He was born 8lbs exactly and after he was born OB was still going on about how "big" he was. It was really starting to peeve me by that point.