I had a Mirena IUD inserted in September 2005. I wouldn't trade it for anything in the world. My periods are non-existent. Woo Hooo. I plan to have another one inserted in September 2010. I did not have an issue with the weight gain. My 15 lb weight gain happened when I started Humira in September of 2008. Not having a period has made my Crohn's much better. I did spot off and on for a few months after insertion, but after that, nothing. I'll be 40 in June. Good Luck.