NuvaRing Raises Blood Clot Risk 56% Over Other Birth Control: Study

Data from a new federally funded study suggests that side effects of NuvaRing birth control may cause women to face a 56% higher risk of blood clots than those who take older birth control pills.

NuvaRing is a form of birth control that is used by placing a small, flexible ring into the vagina once-a-month. The relatively new birth control ring releases a combination of ethinyl estradiol and etonogestrel, which is known as a “third generation” progestin.

Last week, the FDA released data from a birth control study (pdf) that looked at a wide range of newer birth control products for women and compared them to older, proven drugs to determine the risk of blood clots. Newer forms of progestin-based birth control were found to carry a much higher risk of blood clots, or venous thromboembolic events (VTE), than older drugs like levonorgestrel.

Researchers looked at medical data on about 800,000 women from 2001 to 2007, and found that women who used NuvaRing were 56% more likely to suffer a VTE than their levonorgestrel-using counterparts. VTEs can include deep vein thrombosis, and pulmonary embolisms. Women were also at higher risk of arterial thrombotic events (ATE), which can include heart attacks and strokes.

FDA researchers suggested that use of the NuvaRing led to higher sustained exposure to estrogen, which could be the reason the VTE risk is higher. The same study found that drospirenone-based drugs like Yaz and Yasmin increased blood clot risk by 75%.

The data provides further support for claims raised by hundreds of women throughout the United States have filed a NuvaRing lawsuit against the drug’s manufacturer after suffering serious and sometimes fatal injuries from a blood clot. The complaints allege that the manufacturer failed to properly research the birth control ring or warn about the risk of health problems from NuvaRing.

All federal lawsuits over NuvaRing have been consolidated for pretrial proceedings as part of an MDL, or multidistrict litigation, before Judge Rodney Sippel in the U.S. District Court for the Eastern District of Missouri. The first NuvaRing trials are expected to begin next year.