Abstract
The use of oral contraceptives (OC) has been correlated to several diseases, primarily thromboembolic conditions. Whether these correlations represent a causal relationship or a mere statistical correlation based on other variables, depends on whether users of OC differ in other respects from women in fertile age not using OC. We interviewed 519 Danish women, 15-45 years old and selected at random, concerning present and past use of OC, age, occupation, years of schooling, marital status, income, smoking habits, urbanization, and their opinion on the postulated thrombotic risk among users of OC. The data were analysed by methods for multivariate contingency tables.
Opinions on the thrombotic risk, age, smoking habits and, to a lesser degree, regarding income, were directly correlated to the oral contraceptive use. There was no direct interaction between the use of OC and the other variables. Users of OC were younger and smoked more than the non-users and were of the opinion that the use of OC implied only minor thrombotic risk, or none at all.