When is Implanon completely done?

I'm on the birth control called Implanon. and in September2012 was my 3 year mark.. I recently got married and have lost my Medicaid, and my husbands place of work has not gotten around to him for renewing his medical insurance and we currently do not have the money for my doctor to remove it just yet. I know that it's a slow release hormone and doesn't run out just as soon as the 3 years are up. i have tried doing my research on it, but none of the studies posted via Internet say just how long it truly lasts. but if anyone has had it for longer than their three years or knows anything about the Implanon, please let me know. we have started using protection again, but you can never be too safe.