Levonorgestrel
"I used to suffer from extremely heavy periods and cramping that interfered with my daily life. I would have to take time off work, rearrange my entire schedule and in general have an awful time with PMS before my period. Since getting my Mirena, I have had NONE of those symptoms. I finally can live my life without worry that my period will interrupt it. I do not get a period and I do not have any PMS symptoms. It's clear to me that Mirena changed my life for the better."