Hey! My baby weighed almost 4 pounds when I was 32 weeks. They gave me a sonagram and found out that way. Im 34 weeks now (due date Feb.17,2009) and I can tell he has grown alot more! They are doing another songrm next week so I'll be able to find out how much they grow in 2-3 weeks time. I'll come back here and let you know. Well hope this helps. ~~Carrie