The copper IUD can cause problems with excess copper. When copper is not balanced with zinc it causes many symptoms. Why not give the cervical cap or diaphragm a try? I used the diaphragm as birth control until menopause. It worked just fine and was very comfortable. I tried the one with that had a spring but that was too uncomfortable. The flat one was the one that I used. The recommendation is to put about a tablespoon of spermicidal cream in the diaphragm but I found that I could use about 1-2 tsp and then a ribbon of the cream around the edge before inserting. It slides into place quite easily and you don't have to mess with condoms. My diaphragm held up for many, many years before I had to replace it. I never tried the cervical cap, though. I understand that you can get by without any spermicide with that because it fits so snugly. That might be an option for women who are allergic to the spermicide.