How accurate is my ultrasound

[LacyJay]

I had my first ultrasound in May of 2009. It indicated I was 17 weeks 0 days which matched within 2 days of my conception date. So we went with that date because two days was impressive (I know they can't get it exact). At 27 weeks however my baby measured 11 days ahead. The doctor says we will not change my due date bc the earlier ultrasound is more precise. I had another ultrasound at 30 weeks and it matched the last ultrasound. Are my original dates the ones I should go off of even though 2 late scans matched up? I am scared to have a huge baby, but also scared if we go by the late ones that he won't be ready to come out. My doctor says we still go by the original and not to worry.  BTW I do not have gestational diabetes.

[LacyJay]

Thanks for the reassuring words. Being pregnant is so confusing!! I will let you all know how things turn out good luck to you all:)

[hazleyez]

yes i agree with the first two post... the earlier ones are more accurate. :0) Congrats and dont worry they will induce you if the baby gets too big :0)

[hope_peace]

I am soo happy to hear you don't have Gestational diabetes.
I agree with Bny the first earlier u/s are more accurate.. they wont let your baby get to big and if they feel the little one is they might be willing to induce you early.

[bny807]

i believe they say the ultrasounds are more accurate earlier on.. the later you get the more variance you can have, just due to size differences, but maturity is better measured by the original ultrasound and conception date i think! :)   we are measuring almost 4 weeks ahead! she is huge.. but still going by our original dates as well.. GOOD LUCK and congrats! :)