At the hospital for women in Finkenau intra-uterine devices are used since 1965. At first plastic devices were used exclusively. It was assumed that the devices could stay for variable times. The present opinion that non-commper deivces have to be changed at regular intervals is in contradistinction to our first opinion. A questionaire was sent to women who had an intra-uterine device placed for four years or longer prior to the questionaire. The devices were Margulies Spirals or Lippes Loops. It was found that 47% of the patients who answered the questionaire still wore the same intra-uterine device from between 4--10 years after insertion and in some cases 13 years after insertion. 64.2% of the patients wore the same intra-uterine device until it was changed or permanently removed, more than 4 years after it was inserted. This study does not show that a change of plastic intra-uterine devices is necessary when the device is tolerated without side effects.