I just had to go to the dr. for a baseline ultrasound during my menstrual cycle. Day 4 to be exact and it showed that my lining was thin and that I had 14 eggs in left ovary and 10 in the right one. Now when I get my first positive on my OPK I have to go have another ultrasound done. What exactly is that for? I know I should've asked but it's one of those things where I thought about that AFTER I left the dr.'s office. Thanks so much for the help. :)