April 10, 2012 — The U.S. Food and Drug Administration (FDA) has issued a Public Safety Announcement, warning:
“The FDA has concluded that drospirenone-containing birth control pills may be associated with a higher risk for blood clots than other progestin-containing pills.”
The FDA will be updating the safety labeling on all drospirenone-containing birth control pills to include this risk information. Birth control pills that contain drospirenone include: Yaz, Yasmin, Beyaz, Gianvi, Loryna, Safyral, Syeda, Ocella, and Zarah.
The FDA is recommending that women should consult their physician regarding the risk of blood clots before deciding which birth control to use. Although drospirenone is associated with a slightly higher risk of blood clots, it is equally effective at preventing pregnancy compared to other progestins.
The FDA decision comes on the heels of several epidemiological studies which found that the risk of blood clots may be three times higher with drospirenone, compared to products containing levonorgestrel or other types of synthetic progestin. The FDA noted that some studies have not found an increased risk with drospirenone. The new labels will include summary information about the results of an FDA-funded study of drospirenone-containing birth control pills.
The FDA-funded study, which involved 800,000 American women, found a three-fold increased risk of blood clots in women taking drospirenone. In November of 2011, an FDA panel voted 21-5 that the safety labeling on all drospirenone-containing birth control pills was inadequate, and it should be updated to include the conclusions of the FDA-funded study.
Drospirenone is a new, synthetic version of the female reproductive hormone progestin. Most birth control pills contain a combination of synthetic progestin and estrogen, and experts have long known that all progestins slightly increase a woman’s risk of having a blood clot. The risk with older versions of synthetic progestin was around 4-6 women per 10,000. Researchers now estimate that the risk with drospirenone is around 10 women per 10,000.