At my 12 week ultasound (12w1d) I was measuring 11w4d. At my 18 week (18w3d) ultrasound I was measuring 19d5w. I went to the OB two days ago, 24w5d and was measuring, by uterus size, 26 weeks...the other ladies are right, I think they have their own little growth spurts and being a little bigger is nothing to be worried about, though we always find something to worry about, don't we? :)
They just do things at their own pace. I have had ultrasounds where my little guy was measuring way ahead, others a bit behind and some exactly right. I really think they have little growth spurts or something. It's all normal. Congratulations!!!
My baby was measuring ahead in the beginning at first to. I'm now 34 weeks. This was IVF so there is no mistake as to how far along I am. I think you are just fine, Congrats!
Sounds like things are awesome! My baby has measured about 3-5 days ahead consistently. I don't think it means anything... except that I state my due date as "somewhere in the last week of March". :) I've never heard of the baby measuring a few days ahead as being a bad thing.