tokens: Among women who used oral contraceptives , the odds ratio was 2 . 1 ( 95 percent confidence interval , 1 . 5 to 3 . 0 ) for those without a prothrombotic mutation and 1 . 9 ( 95 percent confidence interval , 0 . 6 to 5 . 5 ) for those with a mutation CONCLUSIONS : The risk of myocardial infarction was increased among women who used second - generation oral contraceptives .