If i wasnt able to tell the sonographer my lmp do they tell you the age of the fetus? at my first ultrasound i couldnt remember the exact date of my last menstral period, i just knew the general timing. so i said i didn't know, so does the measurements th

The : The gestational age of your fetus is determined by the lmp. The measurements done by the sonographer of 15 weeks and 4 days is the fetal age (age since conception). I know it can be a bit confusing, but always ask questions if you don't understand something. Your doctor will base your due date on the fetal age given by the sonographer. Best of luck to you!

U/S will tell: The u/s will tell a due date with a fair amount of accuracy, assuming you are still in the first trimester (first 12 wks) of pregnancy.