Effects of changes in smoking status on risk estimates for myocardial infarction among women recruited for the Royal College of General Practitioners' Oral Contraception Study in the UK.

Abstract

Previous results from the Oral Contraception Study regarding the effects of COCs are unlikely to have been biased by changes in the smoking habits of the cohort, but the effects of smoking have probably been underestimated. There is still a need for effective health education regarding the risks associated with smoking, particularly among users of COCs.