Pills Double the Risk of Blood Clots. A new study has confirmed that Yaz, Yasmin and other birth control pills made with the synthetic progestin, drospirenone, are more likely to cause blood clots. The study, published yesterday in the British Medical Journal, found drospirenone birth control pills double the risk of blood clots compared to those that contain an older progestin, levonorgestrel.
The study found similar increased risks with birth control pills containing two other newer, synthetic progestins, desogestrel and gestodene.
relative risk of suffering a blood clot increased sixfold among women taking birth control pills
This new study was conducted by researchers at the University of Copenhagen in Denmark, who reviewed data of the hormonal contraception patterns and first time venous thromboembolism (VTE) episodes for all Danish non-pregnant women between the ages of 15 and 49 from January 2001 until December 2009. Compared with women not using hormonal contraception, the relative risk of suffering a blood clot increased sixfold among women taking birth control pills in women taking drospirenone, gestodene or desogestrel pills. Among women taking a pill with the progestin levonorgestrel, the risk only increased by threefold.
Yaz, Yasmin and other drospirenone-containing birth control pills have become popular because some women tolerate this type of progestin better, and some side effects, like water retention, are less severe compared to other pills. But drospirenone is known to carry other risks. For one thing, it can impact the body’s potassium levels, which can cause a condition known as hyperkalemia, and lead to serious health complication.
FDA decided to review the safety of drospirenone contraceptives
Earlier this year, the U.S. Food & Drug Administration (FDA) decided to review the safety of drospirenone contraceptives after two other British Medical Journal studies reported that pills made with drospirenone increased those risks significantly compared to pills made with levonorgestrel. In addition to the two British Medical Journal studies, the agency also reviewed preliminary results from a study it funded which showed n approximately 1.5-fold increase in the risk of blood clots for women who use drospirenone-containing birth control pills compared to users of other hormonal contraceptives.
In an update issued last month, the FDA said it has not yet reached a conclusion, but remains concerned, about the blood clot risk that may be posed by birth controls like Yaz and Yasmin that contain drospirenone. The agency has decided to schedule a joint meeting of the Reproductive Health Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee on December 8, 2011 to discuss the risks and benefits and specifically the risk of blood clots of drospirenone-containing birth control pills.