It remains unclear whether second-generation oral contraceptives, containing levonorgestrel, or third-generation formulations, containing desogestrel or gestodene, have a more favourable risk profile with regard to myocardial infarction. Third-generation preparations are associated with at least a doubling of the risk of venous thrombosis; however, it has been suggested that they may protect against myocardial infarction by having a more favourable effect on lipid profile. A recent Dutch nationwide, population-based, case–control study enrolled 248 women aged 18–49 years who had a first myocardial infarction (MI) between 1990 and 1995, and 925 matched controls. Use of the OCP was associated with a doubling in MI rates, but the results suggested that second-generation formulations produced a higher risk than the third-generation preparations (OR, 2.5 [95% CI, 1.5–4.1] v 1.3 [95% CI, 0.7– 2.0]). However, the authors note that a previous study suggested the reverse, and that neither study was conclusive due to wide confidence intervals. Among women who had used the OCP, the risk of MI was highest among those who smoked (OR, 13.6), had diabetes (OR, 17.4) or hypercholesterolaemia (OR, 24.7).
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