When your doctor inserts the IUD inside the uterus, the strings, made of plastic threads, are cut about 2 cm from the cervix. To check them, first, wash your hands. Then, while sitting or squatting, insert your index or middle finger into your vagina until you touch the cervix, which will feel firm and rubbery. Feel for the IUD string ends coming through your cervix. If you feel the strings, it is in place and should be working. If the strings feel longer or shorter than the last time you checked them, or if you feel the hard part of the IUD against your cervix, your IUD may have moved. In this instance, you should use condoms and see a doctor. Do not try to push the IUD back yourself. Also, never pull on the IUD strings. If you're worried your IUD has moved, use a backup birth control method until you can see your doctor. Perform a home pregnancy test to exclude pregnancy. If your doctor cannot locate the strings during a pelvic exam, she may order imaging tests like a pelvic ultrasound to confirm the location of the IUD.