Hello there. It is unlikely you get pregnant with copper t but possibilty of ectopic (outside uterus )pregnancy needs to be ruled out if you have missed your period. This is because copper t only protects by avoiding implantation of pregnancy in the uterus due to its presence. Ectopic pregancy is slightly higher in copper t users. You should see your gynecologist to check if your copper t is in place and to rule out possibilty of pregnancy. Dont worry, it is just a possibility. There can be other reasons as well for your delayed period but this is the most important and first thing to be ruled out before other possibilities are kept in mind. take care