K.L.
My Husband and I went through IVF and when I was pregnant a few weeks into it I also had brown spotting. The doctors told me that that was old blood that was part of the lining when the embryos attached some of it may have came loose. I can't say that is what is happening to you, but they told me as long as it wasn't bright red not to be alarmed. I can say I have two beautiful girls to back that up. But, like I said I don't know if this is what you are having. I was scared to death when it happened to me. We had tried for 10 years to have children. I hope this may have helped a little. I wish you all the best.