Scan dates seem wrong

[buntingandstarcharts]

Hi everyone, I had an early scan at what I thought was 7 weeks. They've dated me at 6 weeks and 1 day. It just doesn't make sense as I know when I ovulated (I should I say I know when I had my lh surge) due to tracking my cycles for 6 months. Can anyone shed any light on this? How can there be such a discrepancy? Any info greatly received! Am I at higher risk of miscarrying? There was a heartbeat which I'm sooo grateful for otherwise I'd be mega freaking out. Thanks in advance

I was put back a week with my dates as well. (I had 2 early scans at EPU) I also knew when I ovulated due to tracking. It might be that you took a little while longer to implant. By the time I reached my 12 week scan I was back to the original date I thought I should be. The sonographer said it’s really common and he doesn’t worry about it unless dates are out by 2 weeks or more.

I had similar. All subsequent scans matched my dates that I was approx 12 days further along, but the official records were kept with the first scan date.

This meant my c-section which was planned for "39 weeks" actually happened at over 40 weeks. (Thankfully I didn't go into labour early, as he was 10lb 6oz.)

The embryo is so small, they are measuring such tiny measurements that there is a higher margin of error at this gestation.
It will probably go back to what you expect at your 12 week scan when baby is bigger and measurements are more accurate for dating

The LH surge doesn't always link to ovulation, you may have had a failed attempt at ovulation then ovulated a week later after a second surge - did you keep testing after your first positive OPK/did you temp?

It's entirely normal that successful ovulation could be later than the first positive OPK, doesn't sound anything to worry about. You'll get an estimated due date at your 12 week scan that they will work from

@buntingandstarcharts hiyah,

This happened to me too a few weeks ago and then at my following scan I still measured behind then at my 3rd scan I had oddly caught up and was on track ! Such a worrying thing but it worked out okay. When talking to friends this seemed to be totally normal!

1. A scan date can be a up to a week out. They go by measurememts but they aren't 100% accurate. Anything within that week should be normal progress, those few days difference can be caused by measuring.
2. You might know when you ovulated but you can't know when implantation was. This can easily differ up to 3 days.

It isn't a massive discrepancy.

You know when you had your surge and had sex but it can take a few days to implant and the difference in dates at this stage is tiny, baby is mm long, so I tiny bit of measuring can make a difference.
I had the same thing, knew when I'd ovulated, what days we'd had sex, had a positive really early so was convinced I was due onsay 13th, original early scan agreed then 12 week scan said 9th. And said twins 🤣. I was so worried they'd be prem and they'd be more prem that people realised because they were meant to be on the 13th bit everyone expected them the 9th.
4 weeks early, nearly 7 lb each, perfect and now 10 months and huge.
It's fine op, honestly z

Thank you so much for everyone's reassurance ❤️