Why did an advisory panel of experts for the Food and Drug Administration (FDA) not vote to ban the popular birth control pill Yaz and other pills of its generation containing the hormone drospirenone, instead opting to recommend that the pills carry a stronger warning for life-threatening blood clots?
There is no doubt that with all oral contraceptives there is a slight risk for blood clots. Bayer, maker of Yaz and a family of other drospirenone-containing pills such as Yasmin, Beyaz and Safyral, has consistently claimed its pills were no more as dangerous than other birth control pills.
However, newer studies have indicated the risk of drospirenone-containing pills may be as much as 74 percent greater than older generation hormones, such as levonorgestrel.
Blood clots, also known as venous thromboembolism (VTE), can break away and move to the lungs and cause respiratory distress, to the heart and cause heart attacks, or to the brain and trigger strokes – all conditions that can be deadly. The pills have also been associated with a greater risk for gallbladder damage.
Nearly half of the advisory panel charged with reviewing the safety of Yaz voted that the risks associated with the pills were greater than the benefits. But the slight majority of the panel gave credit to the drug’s other so-called benefits, including treating certain menstrual-related problems and moderate acne.
Some voters also raised concerns that the studies did not adequately take into account factors that could contribute to the development of blood clots such as body mass index, smoking, socioeconomic status and family history. The studies were also observational, not controlled.
The committee ultimately voted 21 to 5 that the labels on dropsirenone-containing pills do not adequately reflect the risk-benefit profile and recommended that a stronger warning should be placed on the pills. The FDA is not required to follow the advice of its committee members, but it most often does.