Among the most popular contraceptive pills available in the Canada - Yaz and Yasmin - carry a higher risk of serious blood clots than some other oral contraceptives, two new studies say.
Studies - both published Thursday in the British Medical Journal Online Edition - show that pills containing a new type of hormone called progestin drospirenone carry up to triple the risk of serious blood clots (known as venous thromboembolisms) on an old generation of pills containing a hormone called levonorgestrel.
Drospirenone is the key ingredient of Yasmin and Yaz, manufactured by Bayer and widely prescribed in the Canada. /
Focused on the drospirenone pills Yaz and Yasmin had global sales of 2 billion dollars in 2009, reports indicated.
Program market from the CBC raised health concerns regarding Yaz and Yasmin in January. Co-Chair Erica Johnson spoke to a number of young women who took the two brands of pills and health problems serious experienced.
More than 4,000 women have taken legal action against Bayer and more than 800 in the Canada joined a class action.
The findings provide evidence that the ancient oral contraceptives "appear to be a safer choice in thromboembolism than preparations containing drospirenone,", explains Dr. Susan Jick, school of medicine, Boston University, who led the research team.
In the first study, the researchers found the risk of a blood clot non-fatal in women using pills drospirenone of was double the risk for women using levonorgestrel containing oral contraceptives.
The study stresses that the overall risk of serious blood clots remains low – even in women taking the pill on the drospirenoane. Incidence rates were 30.8 per 100 000 years of women among the users of drospirenone versus 12.5 by 100 000 years of woman among users of levonorgestrel pills.
The researchers investigated existing U.S. medical claims data to reach their conclusions.
In the second study, researchers have discovered the first non-fatal blood clot risk among women with drospirenone containing oral contraceptives to women who have used the pill levonorgestrel-based almost tripled.
"Prescribe preparations of levonorgestrel risk lower than the choice of first line for women wishing to take an oral contraceptive appear prudent," say the authors.
In a statement, Bayer said Canada "the way the authors applied the methodology of the study reported in these two publications of defects on important show" and maintained that previous studies have shown that Yaz and Yasmin are as safe as other birth control pills.
"In view of the scientific body already large and robust evidence, notice of Bayer, these studies do not change the overall evaluation of the safety of oral contraceptives Bayer," the company said.
Erica Johnson return records the CBC links to accessibility
