I had the Mirena for 4 years (got it when I was 38) and finally had it removed about 1.5 years ago. I gained a LOT of weight while on it (~40 lbs) not because it actually caused me to gain or because it increased my appetite, but because it made it impossible for me to lose. I don't know exactly what happened and why it was different for me than for most (even my doctor is unsure and was doing additional research), but it sucked. Basically, no matter how little I ate and how hard I worked out, the weight would NOT budge. And since for me, maintaining my weight usually means gain a couple of lbs, lose a couple of lbs to stay 'even'...when the "lose a couple" part didn't work, I was on a steady gain pattern for 4 years. It was incredibly frustrating!

This same 4 years coincided with the first 4 years I started cycling and I was actually MORE active than I was prior...so it's not that I got suddenly sedentary.

The final straw was severe and debilitating lower back pain that started to build after year 3. It got so bad at the end that I could not unload the dishwasher. I had to squat to put on pants because bending over and lifting one leg was impossible for me. Sharp shooting pains and complete lower back weakness. I could not bend over and then lift myself up without using my arms to push or pull on something...it was that bad.

I got the IUD out and the back pain was gone within 2 weeks and I started losing weight again (when I finally started to try). My periods also returned in the first two months (I had zero periods while on it even though I could tell I was cycling by occasional mild cramps or skin changes). I'm now 43 and free of all hormones (my H had a vasectomy) and I feel FANTASTIC. My periods are regular for the first time in my life (I was all over the place before I stared the BCP at 21 years old).