Study links birth control pill to arterial plaque

By Will Dunham

ORLANDO, Florida (Reuters) - A European study released on Tuesday has raised new concerns about the safety of women's long-term use of the birth control pill, suggesting increased risk of heart attack or stroke.

Women who had used oral contraceptives were more likely than those who did not take the pill to have a buildup of plaque in their arteries, the researchers told an American Heart Association meeting.

"The main concern is if you have higher plaque levels that you might develop a clot on one of these plaques and have a stroke or a myocardial infarction (heart attack) or sudden cardiac death," Dr. Ernst Rietzschel of Ghent University in Belgium, who led the research, told reporters.

"That's the main risk with having plaque, with having atherosclerosis."

Rietzschel's team studied 1,301 women ages 35 to 55.

Of them, 81 percent had used the pill, for an average of 13 years. The researchers saw a rise of 20 to 30 percent in arterial plaque in two big arteries -- the carotid in the neck and the femoral in the leg -- for each decade of use.

The researchers measured plaque levels using a technique called vascular echography.

In atherosclerosis, there is a hardening and narrowing of the arteries caused by the slow buildup of plaque, made up of fat, cholesterol, calcium and other material, on the inside of artery walls.