At 31 weeks I had an ultrasound and baby measured big at 4lbs! Now at my 33 week appointment she measured my stomach and I was measuring at 29 1/2 weeks and did some calculations and said that ultrasounds are usually off  by 20% each way and would actually put my baby in the 30th percentile. I do have gestational diabetes. But next week at 34 weeks she is sending me for another ultrasound to check babys fluid and weight and then she wants to have a non stress test done. Anyone else gone through this?