To the best of my knowledge copper is only contraindicated in people who are allergic to copper.
I've had good ole coppertop (paraguard) for 8.5 years now... and loooooooove it. I can't use hormone BC because it triggers a very fast acting gynecological cancer in me. That it has a lower failure rate than even a tubal (and works on day 1, for 10 years, through all antibiotics, etc.) is just more icing on the cake. Of course, since it has no hormones, no hormonal side effects. From the icky ones (like cancer for those like me, to weight gain, mood swings, skin problems, etc.), to the nice ones (shorter periods, less cramping, clearer skin) that some people get. Your period resets to "normal" on Paraguard. But it does typically take 2-3 months. Those first 2-3 periods are SUPER crampy (huzzah for midol) and then you just set to "normal", whatever that is for you.
There *are* risks with ALL forms of birth control (like seizures / blood clots with hormonal bc, or the IUD embedding)... but the risks for all approved forms are extremely low. Before getting Paraguard inserted it's generally a good idea to test for a copper allergy.