Yasmin clotting woes continue

New concerns came out late last week about the clotting disorders caused by Bayer’s Yasmin contraceptive. Two new studies show that users of birth control pills which contain drospirenone, one of the hormones used in Yasmin, had a two the three times higher risk of dangerous blood clots than those who used the older synthetic hormone levonorgestrel. This is published on the British Medical Association’s website.

The study sited by the BMA is based on US medical claims data. After researching the numbers, they found that women had a two fold increased risk of non-fatal venous thromboembolism when they used the birth control pills containing drospirenone as compared to those who used levonorgestrel.

These clots occur most often in the legs and can dislodge and travel to the lungs where serious damage, even death, can occur. But even with the doubling and tripling of the risk, the numbers are still small for the occurrences. It happens 30.8 times in every 100,000 women on drospirenone as compared to 12.5 in the control group.

Bayer, as could be expected, argues about the methodology. “Given the already large and robust scientific body of evidence, in Bayer’s opinion, these studies do not change the overall assessment about the safety of Bayer’s oral contraceptives,” the company said. They have been testing and retesting the product for over ten years.

Yasmin is the number two best seller for Bayer, falling behind a medication used for multiple sclerosis.

Source: bmj.com, Reuters