New Studies Find Yaz More Risky Than Other Leading Birth Control Pills: ABC News Investigates

Oct. 14, 2011— -- The blockbuster birth control pill with benefits, Yaz was pitched as the choice for women desperate for relief from severe PMS and acne. But now, new independent studies have found that Yaz carries higher blood clotting risks than other leading birth control pills.

ABC News investigated whether tens of millions of women switched to a more potentially risky pill that, as it turns out, was never proven to treat common PMS.

In 2007, Carissa Ubersox, 24, was fresh out of college and starting her dream job as a pediatric nurse in Madison, Wis. On Christmas day, while working the holiday shift, her boyfriend surprised her at the hospital with a marriage proposal.

Wanting to look and feel her best for her wedding day, Carissa said she switched to Yaz after watching one of its commercials that suggested this pill could help with bloating and acne.

"Yaz is the only birth control proven to treat the physical and emotional premenstrual symptoms that are severe enough to impact your life," claimed the ad.

It "sounds like a miracle drug," Carissa said she remembers thinking.

But just three months later, in February 2008, Carissa's legs started to ache. She didn't pay much attention to it, assuming, she said, that it was just soreness from being on her feet for a 12-hour shift.

By the next evening, she was gasping for air. Blood clots in her legs had traveled through her veins to her lungs, causing a massive double pulmonary embolism.

Her fiance called 911, but on the way to the hospital Carissa's heart stopped. Doctors revived her, but she slipped into a coma for almost two weeks.

Carissa's only memory of that time is something she refers to as an extraordinary dreamlike experience. She said she remembers a big ornate gate and seeing a recently deceased cousin.

That cousin, Carissa said, told her, "You can stay here with me or you can go back."

But, she recounted, he told her if she goes back she'll end up blind.

"I just remember waking up in the hospital and I was like, 'Oh, I guess I chose to stay,'" Carissa told ABC News.

Like her cousin in her dreamlike experience foretold, she actually did wake up blind, and remains blind to this day.

No one can say for sure whether Yaz caused Carissa's blindness, but Yaz contains a unique hormone called drospirenone that some experts say may trigger more blood clots than other birth control pills. Clots can cause serious breathing problems, a stroke or even death.

All birth control pills come with some risk. Two to four women per 10,000 on the pill will suffer blood clots, and some will die as a result. But with Yaz, several new independent studies have put that risk two to three times higher.

"It's a disappointing finding," said Dr. Susan Jick, author of one of those independent studies involving almost a million women. "As a public safety concern that's not what one wants to find."

Made by Bayer HealthCare Pharmaceuticals, Yaz sales rocketed to nearly $2 billion a year after its release in 2006, making it at one time the leading birth control pill on the market and Bayer's top-selling drug.

And there was a lot of buzz surrounding Yaz, from popular women's magazines touting it as "the pill for PMS" and "super pill" to TV news segments, like one in Dallas that called Yaz, "a miracle pill that gets rid of most of the uncomfortable symptoms of PMS."