In a large-scale Danish study of 1.6 million women of childbearing age, researchers found that women who took birth control pills that contained both estrogen and progestin were 1.5 to two times more likely to have a heart attack or stroke than women who didn't use these oral contraceptives.

The risk grew to 2.5 to three times for women who used vaginal rings and transdermal patches that contained this combination of hormones.

Age as a factor

But the researchers were quick to note that the risk was tied to age.

"A doubled risk for thrombotic stroke is not very serious when you are 20 years old, because your risk at baseline is very low," says lead author Oivind Lidegaard, at Rigshospitalet, a state-run hospital in Copenhagen. "On the other hand, when you are 35 years old or older, the risk is no longer that low, and you should be more careful with choosing those products with the lowest risk of thrombotic complications."

New label

Earlier this year, the FDA said that birth control pills that contained drospirenone, a synthetic version of the hormone progesterone, would need new labels warning of the higher risk for blood clots.

That change was aimed at blood clots in veins. The Danish study focuses on the risk for clots in arteries, which can cause heart attacks and stroke.

The Danish study found significantly higher rates of heart attack and stroke among women with diabetes and high blood pressure and among those older than age 35. The relative odds of suffering a heart attack doubled among women 40 to 44, compared with those who were 35 to 39.

Weighing the risks

Kathleen Hoeger, M.D., at the University of Rochester in New York, says that birth control pills are beneficial even if they have risks. "I wouldn't want a study like this ... to tell us these are dangerous drugs," Dr. Hoeger says. "The drugs have risks, and those risks are really well-defined. This data gives doctors a lot of confidence to be able to offer advice."

The study was published in a recent issue of the New England Journal of Medicine.

Always talk with your health care provider to find out more information.

Online Resources

(Our Organization is not responsible for the content of Internet sites.)

American College of Cardiology - Women and Heart Disease

American Heart Association - High Blood Pressure and Women

National Heart, Lung, and Blood Institute - The Healthy Heart Handbook for Women

August 2012

Heart Attack Warning Signs

Women are more likely to have "nonclassic" heart attack symptoms than men. These are the most common warning signals for heart attack:

Pain or discomfort in the center of the chest that lasts more than a few minutes, or goes away and comes back
Chest discomfort with sweating
Pain that spreads from the chest to the arm, neck, or jaw
Shortness of breath, tiredness, or upset stomach; these are particularly common in women

If you are at risk for heart disease and have any of these symptoms, seek medical attention immediately. Time is a crucial factor in a heart attack because the longer the blockage remains untreated, the more heart muscle will die. Also, drugs that break down blockage in the arteries - called thrombolytic therapy - must be given within the first few hours.

Always talk with your health care provider to find out more information.