Multiple pregnancies put mother at heart disease risk

Women who give birth to four or more children are at higher risk of developing cardiovascular diseases than women who have fewer children, says Indian-American researcher Monika Sanghavi from University of Texas's Southwestern Medical Center in Dallas. "This study adds to a body of evidence that pregnancy, which generally occurs early in a woman's life, can provide insight into a woman's future cardiovascular risk," informed Sanghavi, assistant professor of internal medicine and lead author of the study.

One possibility might be that women who have many pregnancies may have more visceral fat (fat around abdominal organs). This has been linked to increased heart disease risk. Another possibility could be that increased cholesterol and higher blood sugar associated with pregnancy may lead to increased risk. "During pregnancy, a woman's abdominal size increases, she has higher levels of lipids in her blood, and higher blood sugar levels. Each pregnancy increases this exposure," Sanghavi noted.

Using data gathered for the Dallas Heart Study, Sanghavi and her team compared the number of live births reported by women in the study with their coronary artery calcium (CAC) levels and aortic wall thickness (AWT). High levels of coronary artery calcification and thicker aortic walls are markers of heart disease that show up before symptoms develop. Women were divided into three groups: One or no live births, two to three live births, and four or more live births. Women who reported four or more live births had a 27 percent prevalence of a high calcium score compared with 11 percent among those with two to three live births.

The trend was similar when looking at AWT measurements. "The associations were not affected by adjusting for socio-economic status or traditional cardiovascular risk factors, suggesting that physiological changes associated with pregnancy may account for the change," Sanghavi explained. "We are learning that there are numerous physiologic changes during pregnancy that have consequences for future heart health," said senior author Amit Khera, associate professor of internal medicine.

This study reminds us of the importance of taking a pregnancy history as part of cardiovascular disease screening, he concluded. After receiving her undergraduate degree in bioengineering from Oregon State University, Sanghavi attended medical school at Oregon Health and Science University. She completed her residency in internal medicine at Northwestern Memorial Hospital and received advanced training in cardiology through a fellowship at UT Southwestern, where she was chief cardiology fellow.

Sanghavi is a member of the American Society of Preventive Cardiology, the Texas Medical Association, the American Heart Association, and the American College of Cardiology. In 2013, she was presented the American Heart Association Women in Cardiology Trainee Award for Excellence.