Gestational Diabetic

So last month I had an ultrasound and the baby weighed 2 pounds more than he should, measure almost 2 weeks bigger and the Dr said he was already 85% ready. I have a second ultra in 2 days, what will happen if he's fully developed and ready when they do this ultrasound? My 3 boys were only 6 pounds, she says if I carry this one full term I won't be able to have him naturally and he'd be over 8.5 pounds. Will the dr induce to avoid a c section?