I've gained 15pounds since Mirena IUD this was placed(18Mths). I'm only 5-2 and workout every single day and watch my carbs and take a very low calorie diet. In spite of this, I still continue to gain weight. I have constant bloating and terrible water retention. All my weight is in my stomach and thighs. My period has decreased tremendously and happy with that part but weight gain is not tolerable.