I had Mirena in for about 1.5 years about a year after I had my son. I thought for sure we were done, but then somewhere down the line, I started changing my mind about it. I had it removed this past March. It took me about 6 months to get pregnant only to find out the baby did not have a heartbeat in late Oct followed by a D&C in early Nov. I have thought about the Mirena possibly contributing to my loss. In reality, it probably didn't because it took 6 months for me to get pregnant, so I had all that time to get back to "normal" and also, in my case, I didn't lose a perfectly healthy baby. My baby never developed a heartbeat and was greatly underdeveloped.

I will never really know though.
Anyway, I do have to say that when I am ready to go back on birth control, I will not opt for another IUD. I felt that while the Mirena was in my body, my mood swings were very intense, and I felt angry a lot of the time. I did mention this to my doc, but I don't think she agreed with me that the Mirena could have anything to do with it, but I think differently.