Etonogestrel
"I've had Implanon for almost 3 years and had it removed today. I loved this birth control because it completely got rid of my period, and cramps. On the pill, I had awful cramps and would spend days in bed, on Implanon, cramps NEVER bothered me. My only complaint with the Implanon was major weight gain. Over the past three years I've gained quite a bit of weight and this is the only reason I'm moving back to the pill. If you're worried about weight gain, do not use  Implanon."