What's with the 3+2 or 5+3 thing?

[Stinkyminkymoo]

dumb Q no doubt (spot the newbie!), but what does 3+2 or 5+3 mean? Have seen it on a couple of posts but can't be bothered to work it out.

:) cheers

3 weeks and 2 days pregnant or 5 weeks and 3 days pregnant

days since last period or after scan, what they tell you.

Since LMP.
They may adjust your EDD after the scan if you ovulated late, but probably not