Dr. Jacobs, I'm 6 weeks and 5 days and have been brown staining on and off for 3 weeks. I notice it happens most when I'm on my feet for a while or I've walked more than 2 blocks. My IVF Doctor says it happens to some woman in the first trimester. My concern is that this week I have stained a substantial amount. My IVF Doc did a sono and blood this morning and heart was beating well and levels were fine. How concerned should I be? It is really nerve racking when it happens.