My last period date is clear but scan is showing a few days difference. I dont understand whether to count from LMP or scan age. How do doctors finally calculate weeks?
You count from the first day of your last period, not from conception, thats the part that confused me at first. So if your LMP was 8 weeks ago, youre about 8 weeks pregnant. I just put my LMP date in a pregnancy app and it did all the counting for me.
My gynac explained it simply, due date is roughly LMP plus 280 days, or take your LMP, go back 3 months and add 7 days. The weeks are counted from that first day of last period. She said the dating scan fine tunes it if cycles are irregular.
Note down the first day of your last period and count the full weeks since then, simple. Both times my doctor used my LMP to set the dates. Just remember its from period start, that catches a lot of people off guard.
Oh I was confused by this too. So we dont count from when we actually conceived? Counting from last period date makes it feel like youre more weeks along than you expect, na.
