Demographic techniques in describing contraceptive use applied on the situation in Sweden.

The authors suggest expressing the amount of use of contraceptives in a female population in the same terms as used to denote the occurrence of births, with one year of contraceptive use regarded as an event in the same sense as a birth. If the prevalence of contraceptives in a population can be expressed in the same terms as other events associated with reproduction, such as births and abortions, it may help to clarify the relationships between these events. Applying the method used to calculate the total fertility and abortion rates on the use of oral contraceptives and intrauterine devices in Sweden in 1975, they noted 1.8 deliveries, 0.6 legal abortions and seven years' use of oral contraceptives and six years' use of intrauterine device per women.