i have had mine for almost 3 years now (due to be replaced in august this year)
to start with i had no period for about 3 months then i got one every 2nd month up till about 2 months ago now i think it could be starting to wear off as i am getting a period every single month and they are different like before i had any contraceptive of any sort, i have a dr appointment tomorrow to discuss it cause i really dont want anymore