June 15, 2012
Could Your Birth Control Cause Heart Attack and Stroke?
(Ivanhoe Newswire) -- A 15-year Danish historical cohort study was done to see how hormonal contraception can cause thrombotic stroke (blood clotting inside a brain artery) and myocardial infarction (heart attack).
In this study, 1,626,158 non-pregnant women from the ages of 15 to 49 years old were observed. During the study 3,311 thrombotic strokes and 1,725 myocardial infarctions occurred.
Using ethinyl estradiol at a dose of 20 µg, the corresponding relative risks according to progestin type were as follows: desogestrel, 1.5 and 1.6; gestodene, 1.7 and 1.2; and drospirenone, 0.9 and 0.0.
For transdermal patches, the corresponding relative risks were 3.2 and 0.0, and for a vaginal ring, 2.5 and 2.1.
Although the absolute risks of thrombotic stroke and myocardial infarction associated with the use of hormonal contraception were low, the risk was increased by a factor of 0.9 to 1.7 with oral contraceptives that included ethinyl estradiol at a dose of 20 µg and by a factor of 1.3 to 2.3 with those that included ethinyl estradiol at a dose of 30 to 40 µg, with relatively small differences in risk according to progestin type.
Source: New England Journal of Medicine, June 2012