Dating a pregnancy from the conception date
Dating a pregnancy from the conception date - dating in the dark couples still dating
Perhaps you’ve been given a due date that seems totally out of sync with the date that you thought you were going to have your baby.Despite the fact that sonographers are experts in their field, estimated due dates (EDD) calculated from pregnancy scans can be incorrect, as Ollysmum76 discovered.
Measurements at such an early stage aren't accurate which is why they wait for 12 weeks to date you.
“The due date is estimated by measuring the ‘crown rump length’ of your baby which is essentially their length from head to bottom. Your baby's growth can slow down and then have spurts.
The healthcare professionals will stick to this date as far as possible because it is then used as the baseline for growth throughout pregnancy." While the professionals like to try and stick with the date that you’re given at your dating scan, it can and does change. "I'm 16 5 and have already been given 3 due dates and its changed for a 4th time back to the 2nd estimated due date! I have scans every few weeks so it will probably keep on changing.
"At my 12 week scan I was back to bang on dates for my last period and was told to ignore the previous two scans, which they said were to check for 'viability' as opposed to dates.
I know it’s hard, but please try not to worry.” Adams Mum also found the date that she was given at an early dating scan was changed when she got to her dating scan.
"From then on he was smack bang on average size for babies EDD on 15 March.
I wouldn’t take an early scan as read, as it’s not your official dating scan anyway.” Well, you'd think so, wouldn't you.
My baby will come when it's ready anyway, maybe weeks before or maybe weeks after my due date." Like MFMer LH86 above, some of these first EDD are derived from early pregnancy scans (pic above).
These can be carried out from week 5 or 6 of pregnancy, which is a notoriously tricky time to be accurate on dates.
Had a pregnancy ultrasound that doesn't match your Estimated Due Date (EDD)?
MFM mums share their stories plus expert sonographers explain why it happens and what to do if you're told your due dates are wrong Listening to MFM mums, it's clear lots of you leave your scan with a nagging feeling that what you've been told that day doesn’t seem quite right.
And yet, bizarrely, after your dating scan at 12 weeks, your due date can get accurate the more pregnant you get.