birth control
"I have to wonder how many of the people posting have used any kind of hormonal birth control before - different people react differently to any medicine, but a lot of the symptoms discussed (e.g. weight gain, slower metabolism) are common side effects of the pill too.  I just had mine implanted 2 days ago, so maybe I need to give it some time, but so far it's great. The procedure was relatively painless, but I've also had two kids, and was near the end of my period, so perhaps that's why I had very little trouble and others have had more.  My doctor said that having it done when you aren't on your period can be pretty painful, because the lining is thicker.  Anyhow, I didn't have any cramping or anything afterwards, and my period's already stopped."