Ovulation tests/early scan dating worries

[Rebecca2323]

Hi, I had an early scan yesterday (at what I thought was 7 weeks) where they found a heartbeat and said everything looked fine. I'm still a bit worried though as they pushed my pregnancy back a week to 6 weeks as it only measured a teeny 3.6mm.

The lady kept telling me it's easy to get dates wrong etc, but I used Clearblue Ovulation tests so I know the day I got the peak ovulation and it said ovulation is usually within 48 hours. But this scan changes that date by a week.

I mentioned my ovulation results to the sonographer and she just looked at me like I was totally crazy and said I was thinking too much about it and repeated that I'll just have got my dates wrong. She said people should stick to the old fashioned method and bin the ovulation tests! I'm sure she was trying to reassure me in her own way but it didn't really work!

Are ovulation tests reliable? Or are early scans not always accurate?

I think that it can be difficult to measure such a small embryo and sometimes they can be out. Even a mm can make a difference of days. That is why they date your pregnancy at 12 weeks, it is easier to measure and much more accurate. So your dates may change again at that point. Try not to worry too much.

Scans aren't always accurate in the very early stages - hence why they wait until 12 weeks to date the pregnancy! However, opk's aren't 100% foolproof either. I would follow the sonographer's advice though and not worry - you'll get a more accurate date at 12 weeks and then that could even change by 20. It's far too early to know exact dates for certain

I had a couple of early scans so far this pregnancy.. Had one where measured 6w3d.. From af I should have been 6w5d.. 5 days later I had a private scan and measured 7w3d ... In my case only a few days of a difference but I've heard of others on here saying they were measuring a week or so behind to then have it changed again at 12 week scan. I think as long as they see a good heartbeat they are happy enough at this point.. Good luck!