Etonogestrel
"Have had Implanon for 4 months now after ditching the Depo shot. (Made me gain 30lbs in one month. Not joking and I'm a skinny person and made no health changes) So far have lost 10 of those pounds on Implanon. Have not had a period or spotting.
THE PROCEDURE: was easy. The Lidocane stings like burning nettles, the rest was easy. Only had a tiny bruise and a tiny scar from the needle (which looks like a mole honestly). 
Side Effects: Only one I've had is achy breasts. Like you don't even want people near them in case they bump into them. All my friends on Implanon have experienced the same thing. 
I LOVE Implanon. Won't change birth control ever again!"