Levonorgestrel
"I have had the IUD Mirena for almost a year.  I wanted a no thought birth control and the thought of no periods was very appealing.  However, after the insertion I had the worst cramps ever. They were so intense I was practically bed ridden for the first month and the horrifying pain continued for at least 3 months after.  I was unemployed and thank God for that because I never would have made it through a day.  I have never given birth but I would imagine it was like labor pains...not your typical period cramp...and it was all day every day.  The cramping has gotten better and I have very light bleeding but I now have bad acne and no sex drive.  I think  also have gained weight (not much, maybe 10lbs).  "