1032 women had their first Copper-T inserted, 204 became pregnant, had an expulsion or a removal for medical reasons (19.76%). Of 299 women with their second Copper-T only 15 reported these events (5.02%). Gross-rates show no difference for pregnancy, expulsion, removal because of bleeding or pain or for other medical reasons in different time-intervals of the first year of use, but in total lower event rates for the second year of use. The risk for pregnancy is not reduced for a woman with her second IUD (second segment). Other events and side-effects are reduced and explain the higher continuation-rate for the second segment. If the second IUD is not inserted immediately after removal of the first IUD, the event rate is again increasing.