The copper IUD works for up to 10 years. One hormonal IUD (Mirena) lasts for up to 5 years. The other hormonal IUD (Skyla) lasts for up to 3 years. Your doctor can remove the IUD at any time if you want to get pregnant or if you no longer want to use an IUD.he copper IUD starts working right away after it is inserted. The hormonal IUD starts working right away if it is inserted within 7 days after the start of your period. If a hormonal IUD is inserted at any other time during your menstrual cycle, you will have to wait for 7 days for it to start working.