A new study released on November 7, 2011 will provide a big boost to Yaz and Yasmin blood clot claims filed in U.S. courts.  The study reviewed the health records of 330,000 Israeli women, and found that the use of Yaz or Yasmin dramatically increased the risk of blood clots, strokes, pulmonary embolisms and deep vein thrombosis.  The study was organized by Dr. Naomi Gronich, of the Technion-Israel Institute of Technology.

This new study will prove significant in the U.S. courts, because all courts require the plaintiffs in these lawsuits to prove, using scientific evidence, that the Yaz or Yasmin birth control pills actually caused their blood clot problems.  Typically, this burden of proof on the causation issue is met using epidemiological studies — studies that compare groups who took a certain drug to groups who didn’t take the drug, and then calculate whether there was a statistically significant increase in the occurrence of a given disease or adverse event among the drug-using group.  If the study proves that the drug-using group was more than twice as likely to develop the disease, the U.S. courts find this evidence to be sufficient proof of causation.

The new Yaz study among Israeli women is important because the results meet the burden of proof required by federal courts.  The study confirmed that among women who do not take birth control pills, only 3 women in 10,000 would develop a blood-clot-related health problem in a given year.  The study revealed that among the users of birth control pills containing drospirenone (of which Yaz and Yasmin are the most common), more than 9 women in 10,000 would be expected to develop blood clots in a given year.  Because the relative risk of blood clots is more than double for Yaz users, the study should help the plaintiffs in these cases meet their burden of proof.

The study is also important because of its massive size. In most epidemiological studies, there is a small (but very real) chance that the results in the groups that were studied would not be representative of all such groups in the general population. This risk of error shrinks dramatically when the sample sizes become very large. The sample size in this study — 330,000 — is incredibly large, and should insulate this Yaz study from criticisms that it might have inadvertently selected an atypical study group. As the studies introduced as evidence obtain higher confidence levels in their conclusions, the studies become more persuasive to judge and juries who will ultimately decide the Yaz lawsuits.

If you took Yaz, Yasmin, or other drosprinenone-based contraceptives (like Ocella), and you developed any blood clot problems while on the drug, you should contact us immediately. To contact us, simply fill out the case evaluation form on this website, or call our toll-free number, 877-728-9607.