Th coil threads come through the entrance of the womb (also known as the cervix) and into the top of the vagina - usually about 1-2cm of coil thread can be seen or felt at the opening of the womb (or cervix). Sometimes partners can feel them. In this case, you can go back to the clinic and ask them to cut the threads shorter.
It is a good idea to feel for the threads yourself - often after a period. This gives you reassurance that the coil is in the correct place. To do this you feel for the cervix at the top of the vagina. It feels like the end of your nose. Whereas the walls of the vagina are rough the cervix is smooth and whereas the walls of the vagina are flexible, the cervix is firm. If you pass your fingers over the cervix you should be able to feel the coil threads yourself.
I have asked Linnea, our illustrator, to draw some images so that you can see the relationship between the coil threads and the cervix if you are interested in more information on this. We should be able to upload these later today.
Many thanks for your question.