My mother had a copper T for many years. She had her last kid at age 26 and had the copper T (having it replaced every 10 years) until she reached menopause with no problems at all. My aunt had a copper T for more than 10 years. My sisters in law both have had them for more than 5 years without complications. I had my first copper T placed after my first child was born and kept it for 4 years. My periods got a little heavier, no cramps. I had the IUD removed to have my second child and got pregnant almost immediately. I got a new copper T placed a few weeks after giving birth. I've had it for almost 4 years and have no complains, except for the heavier periods, nothing major. I'm thinking of having my copper T (no hormones) replaced by a Mirena (has hormones) to eliminate my periods, but I have to research some more.
It's important to have yearly physicals when you have an IUD to make sure that everything is OK, and to have the IUD replaced on time.