So I went in yesterday for my 10.5 week ultrasound.  It was amazing...a tiny little, kicking LO!  Heartbeat was 171, so nice and strong. :)

However, they said I was measuring at 11.5 weeks.  Based on the first day of my last period, I should be 11.5 along, but they moved me back a week at my 6 week ultrasound because of LO's size.  If that's confusing: I should be 10.5 according to that last U/S but now it's 11.5 according to this one.

They are still keeping my due date June 4th (based on 10.5 weeks), but keep calling me 11.5 weeks pregnant, and I'm going in next week for my 1st tri genetic screening test.  I don't know what to think.  Has this happened to anyone else?? 

I think there was confusion with my due date as well, possibly bc of the timing of my IVF treatment.  But it was only a 4 day difference.  Initially, they said I was due 4/14, now they are saying 4/18.  I dunno. 

In any case, I would think it's a good thing if baby is measuring faster than your given week.  Sounds like a strong bean.  It's better than measuring short of your given week. 

I dont have any advice, i just think its weird they are not matching up with how many weeks you are and your DD.  What happens when your a week before your DD are they going to say you 40 weeks ?

I would think they would just pick a DD and stick with it.  Alexis always measured 2 weeks ahead of schedule but they never changed my DD

They did this to my sister with her first too.  I think it can be hard for them to pinpoint sometimes b/c there can be such a big fluctuation from woman to woman on the actual O date.  Like me, I don't usually O until CD18, but someone else with the same cycle length might O on CD12 - so it would seem to follow that my baby would measure smaller b/c I actually O'd later and would have implanted later.  Does that make sense? Same issue with the implantation date - it can be anywhere from 6DPO - 12DPO., another 6 day swing. I have a friend who is a PA and she was telling me before that when she was pregnant with both her daughters that she called the ob/gyn after her BFP and told them she was pregnant but "forgot" when her last period was.  That way they did an early u/s - which supposedly tends to be more accurate than the later ones.  That might be why this did not change your DD this time since you had an early one at 6 weeks.  HTH

this info was really helpful, thanks ladies!  I'm sure they are keeping my DD that same for that very reason.  Since I will be back in the office this week, I am going to ask more specifically.  I bet they are keeping it the same due to the reasons you stated, murphnomore + clips :) 

@dorkmeetsnerd: amen to that! :)