the exact same thing happened to me and i was rushed in for an ultrasound. The sonographer told me that all measurememts were fine except her legs werent measuring' right''. Of course i was freaked out and went on the net which told me a million things that could be wrong. doctor even told me when i asked if baby could have dwarfism that he couldnt say. I was in pieces for days until i got the formal results which measursed aloy better and different again! my m/w est that baby would be 4.5 kg bou turned out 3.2! so never can tell. i was always out with fundal measures at the end and yes, my little one came out just fine. so please dont go looking on the net and try and chill baby will be fine.