So is 13 mm still in the normal range, I was on day 18 of my cycle, the lady who scanned me said oh you get heavy periods, don't you, I said yes then at the end I said does anything need to be done and she said only if you want to put up with heavy periods if not get treatment, she didn't seem at all concerned, I also work with a women who is the same age, she had thickening and her dr said it was age related because everything is winding down, she never got sent for other test, I don't see why I'm any different xxx