I think everyone is different. I had my IUD in for almost 4 years and started having symptoms that I noticed in July of this year and did not have it removed until September. My immune system is so messed up so I have been sick for a month with mono along with my hormones being screwed up. Tomorrow I go to an endocrinologist so I hope he helps me. MY sister-in-law had a thyroid cancer and he took it out she trusts him so I help he understands cause every other Dr. has not.