I tested positive with a home pregnancy test yesterday, and am seeing my doctor this afternoon. I've had Mirena since February 2008, six weeks after the birth of my daughter.
I understand there is a high risk for ectopic pregnancy, and for complications if the Mirena remains in the uterus with the developing baby.
I'm hoping that the original poster may respond with a happy ending to her story, or anyone else that has experienced a pregnancy with the Mirena.