Etonogestrel
"I'm a 16 year old girl, and I've had my Implanon since January 2010.  At first, I really liked it because I didn't get my period again until March. The period that started mid March didn't end until mid April.  I noticed no severe cramps, or mood swings at first.  I then went 3 months WITHOUT a period, with a high sex drive, and feeling really happy.  However, I think I was having mood swings without realizing it. After 3 months of enjoying my Implanon a bad period came, with VERY bad cramps, constant breast tenderness, and as my boyfriend says 'severe jerkiness', that lasted for a month, and it has just ended.  I think I'm back to liking the Implanon. "