I believe the Mirena caused your RA. It makes sense that you developed an autoimmune disease as a result of the silicone in the Mirena. This has historically also happened to women with silicone breast implants. I hope you had the Mirena removed. You are not alone with your symptoms. I had horrible, migrating joint pain, sometimes with swelling and redness, which affected my knees, groin, elbows, shoulders, hands, wrists, and even my jaw. After having the Mirena removed, the episodes of pain subsided in frequency and intensity and I'm about 90% better.