Early Scan Date Confusion?

[bottomsizeofbrazil]

Hello all 😁

F27 first time mum to be after two years of trying. I went for an early private scan today and I am completely confused and a bit worried about the dates. Can anybody reassure me or give advice?

I'll give all the info I can...

The first date of my last period was 27th Feb so from that date I thought I was around 6 weeks 6 days today.

I had been using Ovusense core monitor which confirmed ovulation as 13th February. First positive test was 25th March. We BD on 11th and 14th March only.

During my early scan today they detected a heartbeat (yay!) which I saw on screen but said that baby was measuring at 2.7mm and GA of 5 weeks 2 days.

I questioned the dates and he said that it's 5 weeks 2 days from conception (which would be correct) not from the date of my last period which reassured me at the time but since I've come away I've been researching and don't know if that's right? He didn't seem concerned at all, it's just me overthinking probably.

I suppose my worry is, is it measuring too small for how many weeks it's meant to be?

Thank you in advance to anybody who can offer any advice 😃🥰

I did think it was from your last period (perhaps different places do different things). I went on Wednesday thinking I was 6 weeks plus 6 days but they have said I was 7 + 3 which did make sense as had symptoms earlier this time.

Perhaps call them back to clarify. The lady who did my scan did ask me the date of my last period etc and after that she said to me 'oh do you think you are around 6 weeks 6 days' which was just before she started the scan x

Both pregnancies put me 1.5 weeks back both times. Most ladies I know get put back.
You may know your ovulation date, but conception may have been a few days later and equally the eggs journey can take up to 10 days. I'd go by the new date. X

@cat709 yes I didn't get put back 5 days with first DC x

At this stage the embryo size is a better indication of dates than anything else - the literally calculate the date from the size. It's too early to worry about 'measuring small' etc.

Date of last period is never going to be very accurate. I have irregular cycles due to PCOS. With my first, a panic trip to be scanned for what turned out to be implantation bleeding changed my due date from mid-Feb (based on last period) to late March i.e. around a 6 week gap. The scan (plus blood tests in my case) was much more accurate on dates.

And congrats!

I’ve never known them to measure it from the date of conception. Usually they work it out as an extra 2 weeks added on to the date of conception so that would make you 7+2 pregnant. Which is closer to your original dates.
The dating can be tricky early on as it’s literally mm. You’re better off waiting until around 8 weeks +

I got put back a full week as I ovulated a week later than the "average" - I really wouldn't worry x