Introduced in the 1960s, oral contraceptives have been used by about 80 percent of women in the United States at some point in their lives.
For women without pre-existing risks for heart disease, the early formulations were generally safe, and the newer ones appear to be even safer, but all the risks and benefits are yet to be established, especially as women's lifestyles change and new forms of contraceptives become available, according to specialists in women's heart disease at Cedars-Sinai Medical Center.
"As women use these therapies more frequently and for longer periods of time, there is an urgent need to better understand and minimize associated cardiovascular risks," said C. Noel Bairey Merz, M.D., director of the Women's Heart Center and the Preventive and Rehabilitative Cardiac Center at the Cedars-Sinai Heart Institute. She is senior author of an article in the Jan. 20, 2009, issue of the Journal of the American College of Cardiology that provides an overview of the known cardiovascular risks and benefits of hormonal contraceptives while pointing out areas that require further research.
Reproductive hormones affect the tone and function of blood vessels as well as lipid (fat) levels in the blood. Low estrogen levels have been found to increase risk of coronary atherosclerosis (thickening and hardening of artery walls) and "adverse cardiac events," such as heart attacks and strokes. But the use of supplemental estrogen in hormone replacement therapy has been linked to an elevated risk of blood clots that can lead to heart attacks and strokes.
"Health care providers must evaluate each woman's risk factors, especially those related to cardiovascular health, prior to starting any contraceptive therapy. Although pre-menopausal women have a much lower risk of cardiovascular disease, routine screening for potential problems and follow-up is important," said Chrisandra L. Shufelt, M.D., assistant director of the Women's Heart Center at the Cedars-Sinai Heart Institute and co-author of the journal article.