My baby measuring a week behind

Rose

At my 20 week scan my baby was measuring a week behind but sonographer didn't say anything to me just noticed when I looked at my notes after.

I'm seeing obstetrician next week due to family history of blood clots.

Will obstetrician change my due date or is a week behind not significant enough for a change of due date.

If anyone else had a baby measuring a week behind in the 20 week scan when did you give birth? And did you have extra growth scans?