Oral contraceptives and female mortality trends.

Death rates for Ontario females aged 15 to 44 during the years 1959-61 and 1966-68 have been compared to see if there have been any changes in these rates which might be related to the widespread use of oral contraceptives since 1961. Overall mortality (all causes) has declined significantly during this time, as have the rates for deaths due to child-birth and pregnancy, and from cancer of the uterus. Death rates from ischemic heart disease and cancer of the breast have not shown any significant change, but there has been a substantial increase in the rates ascribed to venous thromboembolism and suicide.It must be stressed that a change in the recorded death rate does not necessarily mean that there has been a corresponding change in the incidence of the disease in question, or that such a change is related to the use of oral contraceptives. However, if oral contraceptives do cause an increase in a fatal disease, the effect should show up, sooner or later, in routine mortality statistics, and periodic examination of death rates may therefore provide a useful starting point for more detailed epidemiological investigation.To assist physicians in counselling patients, a diagram has been prepared showing the relative importance of some selected causes of death in females aged 15 to 44, and the extent to which these death rates have changed since the introduction of oral contraceptives.