I have the Mirena now for two years- I felt slightly uncomfortable for about 4 months, and I experienced spotting (light bleeding) infrequently, for about 6 months, and afterwards my body accepted the Mirena, and I haven't had any heavy mentrual cycle. It is a wonderful product, after the body gets used to it,
and so easy to use- For the next three years I will continue to 'forget' about it, until such time when I need to get a new one!
Pam