Belfie - I had a sizing scan at 36 weeks. My dr had warned me that they can be out by 20% which is huge! So like melbel said could be as much as a pound.

For me my fundal height was measuring over 40cm at 36 weeks so they were concerned. They didn't seem to take into account that I am over weight. I was weight just over 100kg at the time, and I'm only 5'2".

So my scan came back at 8lb 3oz at 36 weeks, which is the same weight Randall was full term! So they were even more keen for an induction.

The dr explained that because the measurements (head circ, abdo circ and thigh circ) were all on the big side which led her to believe that he was going to be big anyway, not because of GD. Buthe had a good fat layer around his middle which was due to GD. SHe said that if his tummy was big but his head wasn't (for instance) then it was probably GD making him chubby.

In the end Ethan was induced at 38 weeks and weighed only 7lb 10oz. Much better than the 9lber they were predicting for me.

So if you have a sizing scan (and you more than likely will I think) don't stress if bubs mesures big.

Good luck today.