Levonorgestrel
"I had tried implanon (made me crazy), paraguard (made me crampy and I felt it during intercourse) and mirena (I felt it during intercourse) so I was pretty much out of options when this came along. The size difference worked out! My tiny frame worked better with it. No pain during intercourse and no weird cramps. I was worried that I would have weird spotting because that has been reported on it, but not me. I had 4 months of light periods, each about 4 days long, super easy. After that I haven't had any periods. I'm not a tiny girl either. 5"2' 160 lbs

Anyways! I love this and highly recommend it to someone who always felt the larger iud's and maybe if you're just sensitive to hormones, like myself.

Love this! Totally plan to get another"