The pill and circulatory disease

Abstract

The authors discuss the evidence from retrospective and prospective studies in support of an association between death from circulatory diseases and the use of birth control pills and consider the public health implications of these findings. Two large prospective studies conducted in Great Britain are most significant; in both studies the mortality rate from circulatory disease was higher for those women who took the pill than for those who were nonusers. Mortality associated with pill use involved a wide range of circulatory diseases. In one of these studies the Oral Contraception Study of the Royal College of General Practitioners (RCGP) women who took the combined pill were 5 times more likely to die of circulatory disease than those in the control group. Duration of pill use increased the risks and for those who discontinued pill use after long usage the rates continued to be high. The death rate from circulatory disease among pill users was higher than the death rate from pregnancy complications among the nonusers. The authors address the question of whether the population of pill users differs in some significant way from the population of nonusers and conclude there is no reason to suspect that the association is spurious. They note that in the RCGP study the results were attained after adjusting for differences in age past health smoking habits parity and social class. In view of the evidence alternative methods of birth control should be considered for all women over 35 and for those women over 30 who either smoke or have taken the pill in excess of 5 years.