Induced abortion: trends in the tendency to repeat, Norway, 1972-1981.

Through the 1970s the number of women who experienced an induced abortion increased in Norway. Thus, the population at risk for a repeat abortion has increased. The frequency of repeat abortions has doubled from 1972 to 1981. However, the annual frequency of observed repeat abortion has been below what could be expected according to contraceptive failure rates. There is no evidence that the liberalized abortion legislation has led to the use of induced abortion as a method of birth control. In order to improve fertility surveillance and to elucidate the epidemiology of induced abortion, there is a need for more detailed and individually based national registration of induced abortions as well as spontaneous abortions.