Worried about CRL measurements

[alibombali123]

Hi Everyone,

I had a private scan at 6 weeks and baby measured 2.8mm crown to rump. After looking at normal measurements for 6 weeks, a lot of websites say that normal measurements are 4-6mm CRL for 6 weeks.

The sonographer said everything was fine and sac was good size etc, but I can't help but worry that something isn't quite right when she measured baby at 2.8mm but normal size should be 4-6mm.

Can anyone confirm which measurements are correct for 6 weeks? Anyone had a similar experience?

 

[danijoanne]

Hey hun my measurement st 6 weeks was 2mm which was behind my dates but I then caught up the week behind I was. Babies just seem to have different growth spurts st different times, I wouldn't worry hun x x

 

[danijoanne]

I was six weeks 5 days along but as baby was only 2mm they dated Mr back to 6 weeks. Sorry didn't make that clear in first sorry x

 

[alibombali123]

Thank you, makes me feel a lot better! I thought I was
7 weeks at the time but my periods have been so out of wack for the last year they said I was only 6 weeks based on those measurements which seems realistic enough - I probably ovulated late or something along those lines.
I'm sure she would have mentioned something if something wasn't right - but still can't help worrying when the Internet says something else! Damn google lol!

 

[jellybean90]

I had a scan at what i was told was 6 weeks 1day and baby was measuring 5.8mm! I knew i was i further on but the sonographer said otherwise. Anyway i had a 2nd scan after some spotting that would of put me at 8weeks 4days....but turns out bubs was measuring 23.5mm now which put me at 9 weeks 1day!! It actually looked like a tiny baby. So im guessing your measurements are fine, dont panic! They grow 1mm everyday from 6weeks x

 

[kat2504]

3mm is the average for 6 weeks 1 day.
I had a scan at 6+4 which was 5.6mm so since the baby is supposed to grow almost a mm a day, that's about right. The hospital dated it at 6+1 but they must be using different charts. By 9 weeks the scan measurements, and my original dates matched up perfectly so the 6+1 dating was incorrect. I knew my dates were right anyway.

This document has charts which show you the average, and the top and bottom end of normal.
https://www.fetalmedicine.com/fmf/2010_27.pdf

 

[x melanie x]

At my re assurance scan baby was measuring 9mm and they dated me at 6 weeks and 6 days, 4 days behind where I thought I was. They did say it is very hard to be accurate so early on, so to wait until 12 weeks to get an accurate EDD. Don't worry it'll all pan out as you go along xx

 

[ace28]

I wouldn't worry too much either- though I know it's hard not to.

We *know* our dates and so far at two scans baby has measured behind (one at 9w1d and one at 10w1d). But the doctor's aren't worried- they said that they tend to curl up a lot at this stage anyways, making them very hard to measure!

So just picture your snuggly baby all curled up and happy in there, and try not to worry.

 

[alibombali123]

3mm is the average for 6 weeks 1 day.
I had a scan at 6+4 which was 5.6mm so since the baby is supposed to grow almost a mm a day, that's about right. The hospital dated it at 6+1 but they must be using different charts. By 9 weeks the scan measurements, and my original dates matched up perfectly so the 6+1 dating was incorrect. I knew my dates were right anyway.

This document has charts which show you the average, and the top and bottom end of normal.
https://www.fetalmedicine.com/fmf/2010_27.pdf

I used the chart that kat2504 provided, sonographer estimated me at 41 days gestation and the chart said it should be 2.9mm - so I suppose 2.8 is normal too!

I hate google and all the different numbers it throws at us!

Thank you ladies xxx