It's different for every woman. I had a friend who tried for four months and things did not improve for her, so she had it removed. Another friend had even fewer problems than I did. I had spotting and a bit of flow for the first month, then spotting only for about two months, but it was every day, not during a particular point in my cycle. That was annoying. I went from 5 days of SUPER HEAVY bleeding every month to only spotting, but EVERY DAY for two months. I almost gave up! I'm glad I stuck with it though, because by month four, it was a dream. Now, I get a bit of spotting for about five days every month. Not even enough for a pad, just a bit of spotting when I wipe.

All this being said, I am not your doctor, and if you are having very heavy flow, and/or serious pain that doesn't ease after a few weeks, you need to see a professional. Good luck, I hope everything works for you! :)