I don't have any info other then my personal experience. I have one, and have since Dec 2008. I like that its easy, with nothing to remember or to do besides check the strings. I don't like that I have cramps my entire cycle that vary in severity from mildly uncomfortable to one time sending me to PatientFirst (I gave birth on pit w/o pain meds). Generally it's fine, I don't experience the heavy bleeding I read about on line. I decided to give it a year before ruling it out because for my family it's about our last shot save abstinence for many reasons, which sounds like no fun to me.

hth.
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