I went off them just about a month ago because I couldn't handle the fact I was gaining so much weight. In one months time being off them I lost 8 pounds. I returned to the dermatologist today and decided to start Accutane, another acne medication. But I can't go through the fact of gaining so much weight and feeling so moody and sick. I just don't feel happy due to it.
All oral contraceptives can cause weight gain.
It sounds like your weight gain was more fluid retention. That is good because that corrects itself pretty easily if you don't stay on the pills. When you go back on the pills you might try a different pill that is not quite so strong. The ones used for acne usually have more estrogen and for just birth control you might get by with a milder one with less estrogen and therefore have fewer side effects. You and your doctor can discuss this.