Baby measuring big early on

[JFTB1177]

I just had my NT scan and 1st trimester screen yesterday. Baby looked healthy but was measuring 12w6d when by conception date I should have been 12w2d or 12w4d by lmp.

What does it mean if a baby is measuring ahead early on?

[finnegansmom]

That's just a couple of days, I wouldn't worry at all - it's well within the normal range.

DS#2 measured a full week ahead of my latest possible EDD at my 12 weeks nuchal US, and he was born at 41 weeks. My latest US at 10 weeks had my baby measuring 5 days ahead. It's fine, there is so much margin of error. The only thing I wouldn't do is change your due date to earlier....you don't want to be pressured to be induced...

[MaerynPearl]

nothing at all... scans are not 100% accurate and at 12 weeks could be off by several days without any issue at all.

at 9 weeks my scan was 4 days behind. Baby is just fine and I am 100% positive I know when I ovulated (and thus baby was most definitely conceived then)

[lillymonster]

Mine was measuring a few days ahead at dating u/s, then NT u/s was measuring enough ahead that the OB (not my normal doctor) kept questioning me on my LMP

I am really not worried about it though. I don't know if it matches more with my ovulation date, but that only changes the date by 3 days

[myk]

mine's definitely further ahead. i'm 13w2d (and i know that FOR SURE because i was using ovulation predictor strips, temping, etc) and baby's head measured 14w4d! i'm not going to worry too much about it, but it is definitely odd. it measured perfectly at 7w.

[babymango]

Don't worry about a couple days, it's well within the norm. Ultrasounds are not that precise.
At my 13 week US, the tech was saying how after 9 weeks, babies start to take on their parents characteristics already. A baby with small parents may start measuring slightly smaller than average for instance (within reason of course).

[~Adorkable~]

i was told that even at its most accurate time of the pregnancy (early on) the scan dating is give or take 5 days. so your few days is not a concern at all

[JFTB1177]

Thanks guys!

[dakotablue]

Just wanted to add. Its not that they aren't accurate in measurement as much as babies have growth spurts at different times and some babies are bigger. So if you had the US two days before its possible you could have measured 'behind.' That's why they have their range of still normal for this date. I think 1-2 week range in either direction is what they expect/ accept at 12 weeks.

DS measured 2 weeks ahead at 20w. I think 1 1/2 weeks at 12. He was born 8lbs 9oz at 40w 1d via c sec...I don't think he was even ready then.

[myk]

Originally Posted by babymango

Don't worry about a couple days, it's well within the norm. Ultrasounds are not that precise.
At my 13 week US, the tech was saying how after 9 weeks, babies start to take on their parents characteristics already. A baby with small parents may start measuring slightly smaller than average for instance (within reason of course).

that's good to know my husband has a big head. i've got a bigger head compared to the average of my family. so if this kid has a big melon, it might not be a big deal eh? i was surprised that it was 9 days off.. 5 days off i would not have thought twice about, but more than a week made me