abnormal uterine bleeding
"I've had my Mirena for over a month now. Insertion sucked, but I had some kind of small blockage in my cervix that the Dr had to poke through (he said most women don't have that). I bled for a couple of days after, but didn't experience any real spotting or cramping until my first period. I had to call in sick to work one day because of the pain, but it still wasn't as bad as my pre-Mirena cramping. I haven't stopped bleeding since, but it's very light. I know this can happen for the first few months, so I've committed to a full year before I start wondering if it should be removed or not. I'm very hopeful that Mirena and I will have a good, long relationship though."