CRL Query

[GeneralLilac]

Hiya!

I just have a quick query regarding crown rump lengths...

I had my first scan at what I thought was 7 weeks exactly. According to my ultrasound, my CRL was 15.2mm and (direct quote from report) "this is consistent with a gestation age of 6w2d".

What worries me is every single article/piece of information on the internet says this is more consistent with a GA of 7.5 - 8 weeks.

Can anyone offer any advice? Obviously this is not a huge deal, ultrasounds can be out, I just feel like 15.2mm is massive for 6w2d. It's kinda bugging me the more I think about it!

Thanks, I hesitated posting this because I feel a bit silly

 

[Celesse]

Fetal age is mm + 6 weeks from everything I've read. https://www.baby2see.com/development/ultrasound_sonogram/first_trimester_scans.html

So a 6+2 embryo would measure 2mm.
And an embryo of 15.2mm would be 6 weeks plus 15 days, or 8+1. Now assuming they always round up that gives you 8+2.

And since ultrasound techs are never consistent with if they mean Xweeks Xdays since conception or Xweeks Xdays since LMP it could very well be that they mean 6 weeks and 2 days since conception.

 

[lazymum]

I had my u/s at what I though 7 weeks but was told I am only 6 weeks because the baby measurement was 4.5 mm.
With my previous pregnancy at 7w6d my baby was 11.4
My guess is also that they gave you fatal age since conception not gestational age which calculated from LMP. If so you will be indeed over 8 weeks.

 

[Celesse]

The alternative is they don't mean CRL, but mean sac size. Sac size, mean sac diameter in days is 30 + MSD.
So that would be 30+15.2, which gives you an age of 45.2 days.
This is 6.4 weeks. 0.5 of a week is 3.5 days so assuming they are rounding down this time it could give you somewhere around 6 weeks 2 days.

Do you have a picture of the scan?

 

[GeneralLilac]

Ahh thank you for your replies! I did think perhaps he was noting the fetal age, but he's put my estimated due date at 25 July 2014 and when I did the maths it just didn't seem right that 6w2d would be the fetal age (scan done on 2 December... I can't do the maths now it's 5.30am!). I think I'll just wait until my first trimester scan to see if that ultrasonographer can shed any light (I'm going somewhere different for that one).

Thanks again for replying xo

 

[GeneralLilac]

I have a hard copy picture of the scan and

OH my goodness, genius. I think it's a typo on the report My actual scan states GS: 15.2mm and CRL: 6.8mm oh that seems much more "normal". Ultimate embarrassment *crawls under rock*

 

[Celesse]

Glad you got your answer