I had mirena for 3 in a half months. While I had it I had horrible cramps, heavy bleeding. On the last month I missed my period at first thinking nothing of it. A week later dreadful body achs and began bleeding very heavy. I went to a clinic and was told it was a possible miscarage because it mad moved. I couldnt get a straight answer due to the clinic not being able to do a blood test. After suffering extreme amounts of pain I had it removed. I hope this helps, I have heard that alot of users have no problems.
Well, I havent had Mirena but I know of a few ladies who have. One pf my friends in particular just went to the Dr and found out she has a large mass possible because of it. This is not the first time I have heard of this happening to women. Like I said, I have never tried it but because of the things I have heard, I would check all of my options before deciding. Best of luck to you!