Quoting Katlyn Bell:" Ok. so her weight could either way. But I'm also a little concerned because @ the big sonogram I had ... [snip!] ... weighed 7lbs 1oz & was about 19.5in. My doc hasn't really told me what he thinks she weighs or anything along those lines."
I started measuring 3 weeks behind at 30 weeks. For every 3 weeks, my son would grow for 1 week. He was IUGR. Born at 36 weeks 5 days, but he only measured between 33 weeks on the ultrasound. Ultrasound predicted him to be 4 lbs 2 oz, he came out 4 lbs 15 oz. No NICU, no oxygen, we were released a day early even!
Don't worry about weight until you have to worry about weight.