The Pill: Is Newer Better?
July 20, 2001 -- Six years ago, media reports surfaced suggesting that some newer birth control pills could increase a woman's risk of potentially serious blood clots. In a new study, British researchers have not only confirmed the risk, but say the risk is nearly double that of older birth control pill. Nonetheless, experts assert that the health risk is small, and the Pill remains one of the most effective forms of birth control available today.
An estimated 70 million women take some form of the birth control pill daily. The Pill contains two synthetic hormones, estrogen and progestin, that work together to prevent pregnancy.
Since the early 1960s, several studies have found a link between the Pill and an increased risk of blood clots. Over time, the risk decreased with the introduction of a lower-dose pill. But in 1995, several studies reported the risk of blood clots was again on the rise from the newer "third-generation" pills.
The third-generation pills in question are those containing estrogen in combination with the progestins desogestrel or gestodone. These versions of the Pill are used less frequently in the U.S., where estrogen in combination with norgestimate is more popular.
Concerns of the increased risk were so great that following the reports, use of third-generation pills in the U.K. decreased by as much as 40%. And unfortunately, the women most likely to stop taking it out of fear of blood clots were those under age 30 -- the group most at risk for unintended pregnancy.
Third-generation pills gained popularity because they have been shown to reduce acne and excessive hair growth. They also do not adversely affect weight, blood pressure, and blood sugar levels. And women using these newer pills reportedly have less breakthrough bleeding and spotting.
In the new study, published in this week's British Medical Journal, researchers from the University Medical Centre Utrecht in The Netherlands analyzed 13 studies of third-generation pills and blood clots. They looked for reasons other than the pills to explain the increased risk of blood clots and found none.
Jeanet M. Kemmeren, PhD, and colleagues found that these pills are responsible for an approximately 70% increased risk of blood clots. Women using third-generation pills for the first time had the highest risk of blood clots.
David Grimes, MD, is clinical professor of obstetrics and gynecology at the University of North Carolina at Chapel Hill. "My suggestion to patients who are worried about this is let's use a different pill," Grimes tells WebMD. "There are many, many pills to chose from, and if you are concerned about this, you certainly have many other options."
In an editorial accompanying the new study, James O. Drife, MD, of the General Infirmary in Leeds, U.K., points out that the risk of fatal blood clots while taking third-generation pills is actually less than the risk of blood clots during pregnancy. He says many doctors are "still angry about the amount of human misery" caused by the media frenzy suggesting these pills were dangerous.
Drife also says people should bear in mind that women still die during childbirth and that the risk of death associated with pregnancy is actually 100 times higher than the reported risk of blood clots associated with these pills.
"A 70% increased risk of a rare event is still a rare event," adds Grimes. "But again, if women are concerned about a particular group or brand of birth control, I would advise them to use another one. Newer isn't always better, and there is nothing wrong with using the older pills."