First trimester ultrasounds are done not only to confirm pregnancy, but also to "date" the pregnancy. In fact, dating ultrasounds are much more accurate when done in the first trimester than when done later, so if a woman comes in without knowing good dates, a dating ultrasound can be done right away and can give very accurate dating of the pregnancy.
Originally Posted by RedCatWaves
I found out I was 7w, 2d pregnant with my daughter by ultrasound.