Early scan date and lmp out by 2 weeks how does it affect 12 wk scan?

[alien11]

Hi all

As title suggests I went for an early scan when I thought I was 7+5 going by lmp. Then the sonographer dated me as only 5+6. I had been having 35 day cycles so she said I must have ovulated super late.

I'm just wondering how this will affect dating scan as I thought I would be 12 weeks mid march but if use early scan I would 12 weeks 2 weeks later. Am I right in thinking mw will book scan going by lmp? As otherwise going by the early scan i would be missing the period for the tests?

I've been worried since being told I'm practically 2 weeks behind dates so next scan has me all nervous anyway!

Has anyone had the same thing?

Yup, I had similar! Had a 5 week scan and they moved my dates forward 4 days but they had my 12 week scan booked in by my LMP dates and at that scan redated me again as 10 days out. Much more accurate to date at 12 week scan, so I doubt they'll use your new scanned dates on early scan until they've done the 12 week scan- but of course each trust is a law unto itself!

Thank you! I would presume my 12 wk scan will be as I originally thought then. Hopefully that will be the case around here !

You will go along to the 12 week scan according to your LMP. If it is too early for them to do any testing or measuring they need to do, they'll ask you to come back.

Do you have a repeat early scan to check progress?

Congratulations btw.

With a 35 day cycle, it's likely that you ovulate later in your cycle than the day 14 presumed by LMP dating. If you have an average luteal phase (time between ovulation and period), then you will be at least a week behind on LMP date.

Hi showy

I don't have another early scan so will just have the 12 wk scan which will be sooner as thought they would go by the early scan. So hopefully be around 3 ish weeks!

i had this as i also have 33-35 day cycles.

at what should have been 7+6, a private scan dated me at 6+1. i then had to go to a&e for a scan a few days later following some spotting, where they put me down at 6+5 - but left the appointment for my 12 week scan (which was ironically being booked on their system at the exact same time i was in the a&e department!) in place, as they said it would be fine so long as the baby was over 10 weeks by the time they did the scan.

Thanks scared
Hopefully have scan at original 12 wk ??