A new study finds that women who have had one or more miscarriages are at increased risk for hardening of the arteries (atherosclerosis), which can lead to problems such as heart attack and stroke.

The study presented at the American Heart Association annual meeting in Los Angeles this month.

Researchers looked at health data from more than 1 million Danish women to examine the association between miscarriage and heart attack, stroke, or renovascular hypertension, which is high blood pressure caused by narrowing of the arteries that carry blood to the kidneys.

Compared to women who had no miscarriages, women who had one miscarriage were 11 percent more likely to suffer a heart attack. The risk more than doubled in women who had four or more miscarriages, according to a heart association news release.

Women who had one miscarriage had a 13 percent increased risk of stroke, and those who had four or more miscarriages had an 89 percent increased risk.

Women who had one miscarriage had a 15 percent increased risk of renovascular hypertension, and those who had four or more miscarriages had nearly quadruple the risk.

Each additional miscarriage a women had led to a 9 percent increased risk of heart attack, a 13 percent increased risk of stroke and a 19 percent increased risk of renovascular hypertension.

Although the study found an association between number of miscarriages and certain heart risks, it did not prove a cause-and-effect relationship. Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.