Etonogestrel
"I've only had Implanon for 6 months. They say anything can happen so they can't tell you much about your period. But, in my experience I've had no period so far and no cramps or PMS symptoms. 

I don't believe the Implanon made me gain weight. I was gradually gaining my Freshman 25 in college from September-May and I got the Implanon in January. It didn't make me gain weight abnormally. I just continued my weight gain from eating such unhealthy food at school. Since then, I've lost 17 pounds and I don't believe the Implanon has slowed down any of the weight loss.

Unfortunately, reviews are not going to help you because Implanon is strictly person to person, when it comes to side effects. In my case, I love Implanon!"