My experience with Mirena has been great! I previously had extremely heavy periods (we're talking soaking an overnight pad in an hour) and Mirena solved that problem--I have almost no period at all anymore. My five years just came up, and I had it replaced. Any "side effects" I've experienced I have attributed to perimenopause. I'm 42 years old, and early menopause runs in my family, so any minor weight gain around the middle, low libido, headaches, I attribute to that, since my doctor's office has confirmed low estrogen through blood work. I love Mirena and plan on continuing with it!