It only has 0.4 mg progestin in it. I always thought the higher the progestin, the more chance of weight gain. Maybe that's just the way I am because I gained weight in the exact same way that you are (slowed metabolism) on Estrostep Fe and the progestin in it is 1.0 mg. Also, I was just looking at a table that shows pill problems and what to do about them, and it does state that if you're having weight gain to switch to a pill with a lower progestin.