[The diagnosis and removal of obscure intrauterine devices (author's transl)]

When the thread of an intrauterine device cannot be seen in the cervical canal a diagnostic procedure to insure continued contraceptive effectiveness is mandatory. Hysteroscopy is the method of choice for localization of an intrauterine device even during pregnancy. Hysteroscopic removal is possible even during pregnancy. With this method we removed 16 obscure intrauterine devices and 7 devices during pregnancy. The advantages and disadvantages of other diagnostic and therapeutic methods are discussed.