A new study found that contraceptive skin patches and vaginal rings increase the risk of serious blood clots.
The study found that both methods raised the possibility of clots more than the contraceptive pill.
Fox News reported that the Danish study analyzed 1.6 million women using various contraceptive methods over a 10-year period.
Researchers found 3,434 confirmed diagnoses of venous thrombosis, a vein-blocking blood clot, reported CBC News.
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The patch, it was found, increased the risk of a blood clot by 2.5 times more than those taking the pill.
The risk compared with those who did not use hormal contraceptive at all was six times higher for the vaginal ring and eight times higher for the patch.
This means that about one percent of users will have blood clots over a decade of use.
According to the Boston Globe the researchers concluded that “women are generally advised to use combined oral contraceptives with levonorgestrel or norgestimate, rather than to use transdermal patches or vaginal rings.”
The study was published Thursday in the British Medical Journal.
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