Levonorgestrel
"I was SO nervous to get the Skyla in. I was shaking. I got it in on my third day of my cycle because my doctor it was easier. BARELY FELT ANYTHING. It wasn't even painful, just a little uncomfortable. The "worst" part of it was the clamp, it felt like a pinch. But I was familiar with the clamp because I've had 2 papsmears before. Don't let the bad reviews scare you. I would do it 10x over. I was able to drive myself home, no horrible cramping, etc. I'm 5'9" and 125 pounds."