Levonorgestrel
"I am really worried about all of the negative side effects that everyone keeps talking about, only because I already had them before I got Mirena put in. I just had Mirena put in two days ago, I was on the third day of my period, and it was heavy enough for super tampons.  Now, two days later, it's not even heavy enough for alight tampon, I've been wearing a liner since I had it put in.  The process of getting it was nothing. The doctor kept telling me that I might feel a cramp.... nothing but a tiny pinch. Overall it went very good for me. I went out in the waiting room for a few minutes and was reading a magazine. Felt a little carsick, but that went away in less than a minute and hasn't been back since."