In the case of Implanon, there are so many problems we are not even sure all are known yet; such are the risks of new drugs (and yes I know 13 years is more than a week, but nowhere near enough time to determine the long term effects of extended hormone therapy.) http://en.wikipedia.org/wiki/Implanon#Side_effects_and_risks

There is always Depo Provera, but when most of the critics are womens health groups (generally inclined to SUPPORT easy safe contraception) that raises huge red flags for me. http://en.wikipedia.org/wiki/Depo_Provera#Controversy_over_approval_of_Depo-Provera_in_the_United_States

With the IUD I expect you are up against the Hippocratic Oath; were I a doctor (which I obviously am not,) I would be reluctant to help a patient do something with significant, if small, risk of causing serious permanent harm despite a host of safer alternatives. If you decide next week, month or year you really REALLY want an IUD instead of what your current doctor gave you, you can probably find a doctor who will give you one (in fact, I would bet you already have. ) On the other hand, if you decide in 15 years you really REALLY want tays baby but you have been sterile for a decade: Too bad. I know which I would want on MY medical conscience.

Still your choice of course, but it is that recurring recent theme: The doctor cannot forbid you doing it, but has every right (perhaps even an obligation) to refuse to facilitate it. If you tell your GP to help you grind up heroin to snort so you can avoid AIDS from sharing needles, he will probably still suggest methadone treatment.