Has anybody else had a problem with scans & dating 1 week ahead in pregnancy???

[baby5811]

Just curious to any other people who have had the same problem has i'm having now,All through my pregnancy even from my 1st dating scan which dated me at 11wk 4d i have been dated 1 week ahead,Know when ovulation happend as used OPK and only dtd 1 day in that month and got a pos preg test 2 weeks after the night doctor dated me at 5wks and he msut of been right even though he dated me at a 28 day cycle...Never have i had a 28 day cycle so therefore i cant understand why i am being dated this way and why scans would say i was futher into pregnancy than i actually am?? I seen my dc and mw about this and they said nothing but "they would go from dated given on dating scan and nothing else" regardless of me knowing my dates are incorrect...Am i right in thinking scans are promgrammed to a woman having a 28 day cycle which happens to make woman have a due date that is wrong? Or could it just be that at 11wk 4d my baby was measuring longer than usual????

 

[stardust599]

Hey hun

You'd be best putting this into First Trimester, it's awful quiet in here!

When they first date your pregnancy they'll base it on a 28day cycle which is stupid as I've always had a 35day cycle! Then they use the scans to determine the accurate age of the baby. They go by the "crown to rump" measurement if I remember correctly. And all babies measure the same size up until past 13 or 14 weeks. But the person who does the scan can get the measurements out. Even 0.1 of a millimeter can make a difference. I'm sure the lady made a mistake at my dating scan as she put me a week further ahead than I thought I was and this is the dates they used through my whole pregnancy, then later on they said my baby was too small so I was induced at 38 weeks and I think I was actually only 37weeks which would have meant she wasn't measuring all that small.

If you know the exact date you ovulated your due date should be around 38weeks from that date. But remember that it can vary a bit because it could have been quicker or slower than the average pregnancy to fertilise or implant so that would put your dates out by a few days or so.

xx