I used to have really regular periods on it. Then they slowed down and I think its been about nine months since my last one.
I felt like my period was going to start tonight- migraine, cramping, leg aches- but didn't believe it until I went to the bathroom - twice- and there it was! They are much lighter on the Mirena, but its definitely a period. Woot! It seems silly, but it is SUCH a relief from the PMS! Funny thing is, I'm getting it out in August when I go for my yearly and getting the Essure- I guess they'll take the IUD out right before doing the Essure procedure, actually. It will be 5 years this August anyway, and that's how long this one was supposed to last.