Levonorgestrel
"I got the Mirena in August of 2012 after having our 3 little blessing since then I've had weird periods one month, I bleed almost a month then wouldn't have one for 2 months and when I did have a period it lasted over 10 days.  The past few months I bleed after intercourse and is very painful afterwards and hubby doesn't understand why I don't want to anymore. Also sharp constant pains in my lower abdominal area."