Dating scan dates seem wrong?

[AshleighR]

Hi, I went for my 12 week scan last week and was told i was 12 weeks and 6 days but my last period was on the 5th Nov and i have worked out that i would have been pregnant 3 days before my period and there would have been no chance of getting pregnant until 15th Nov has this happened to anyone else?

[Blue321]

Hi Ashleigh, my best friend is pregnant and while mine follow a normal pattern, hers alter the date each time. We were due on the same day and, while my date is the same, now she is predicted to have her baby two weeks earlier! They are dating the baby to predict the due date, rather than the other way round. They do this by fetus size measurements. Each baby and mother is unique, growing at different rates to achieve different sizes, so it is just a guess for the due date and nothing to worry about. Hope this helps x

[lottiesmum]

This happens to me too and I find it irritating. It really doesnt matter unless you get to 14 days over and you dont want to be induced. I would indicate how you feel to your midwife now but in my experience it wont change anything and bear it in mind if you go overdue. Loafs of people will be in the same boat. Hope this helps.

[boboroho]

Congratulations on uour pregnancy. My first scan put me a week ahead also. After a lot of thinking I eventually got my head around how it works.......a 40 week pregnancy is dated from the first day of your last period but that assumes that everyone's cycle is the same and its not, the reason your are ahead is because ovulation did not occur 2 weeks after your last period but probably more like only a week to ten days after, therefore making you further along in your pregnancy. The measurements in your 1st scan are accurate and you should work with the due date they gave you at it.