I had my Mirena for 3 1/2 years and started getting that feeling nauseous more and more frequently over this past spring (along with many other side effects.) I had mine removed on 4/17 and have not been nauseous since. You may be suprised how different you feel once it is out. I feel healthier and more energetic with only a few short lapses of a couple of side effects as the hormone works itself out of my body.
Good luck to you this week!