The cardiovascular health of pregnant women of color tends to be lower than those of women who are white. For example, women who identify as Hispanic or as Black are also at a higher risk for preterm birth and preeclampsia. Researchers at Northwestern University wanted to try to uncover the root causes of this disparity. What they found out may surprise you. It turns out that the Number One influence on heart health was level of education.

It's such an important factor that the authors of the study concluded that if there were no disparities in education, it's possible that equality in cardiovascular health could be achieved. This means that biological differences aren't driving heart health during pregnancy as much as the number of years of education.

The overall aim of the Pregnancy Outcomes Study was to look for characteristics of mothers that predicted health problems during pregnancy and birth.

“If racial and ethnic groups achieved the same average years of education, the gaps in heart health between the groups could be substantially reduced,” Natalie A. Cameron, the first author of the study, a Northwestern Medicine physician, and an instructor in the Department of Medicine's Division of General Internal Medicine, explained in a press release.

But it's not exactly a straight line from point A to point B. “The pathways linking education to heart health are complex and may be related to income, health insurance, access to healthcare and health-related knowledge,” Cameron explained.

This picture came into focus when the Northwestern scientists analyzed data that was collected during the start of pregnancy from over 9,100 participants who self-identified as either Hispanic, non-Hispanic Black or non-Hispanic white and were part of the Nulliparous Pregnancy Outcomes Study. The overall aim of the Pregnancy Outcomes Study was to look for characteristics of mothers that predicted a health problems during pregnancy and birth.

The Northwestern team began by calculating the participants' cardiovascular health scores based on their: 1) blood pressure, 2) body weight, 3) exercise levels, 4) diet, 5) smoking, and 6) behavior and sleep.

After seeing how scores differed among the three racial groups in the study, the researchers analyzed individual and neighborhood level factors the women reported to learn what might be behind the differences. These included things like maternal age, education, income, health insurance, mental health, racial discrimination and neighborhood deprivation.

The last category, neighborhood deprivation, is a measure of how many people in a neighborhood have low income, low education, or are unemployed. It can also include factors like poor living conditions and high crime rates.

The statistics revealed that individual neighborhood-level factors explained all the differences in cardiovascular health between Hispanic and white participants, and 82 percent of the differences between Black and white participants.

The scientists discovered something else: educational attainment had the largest impact on cardiovascular health disparities. The result is part of a growing body of evidence showing how social and environmental factors affect the health of the people living in an area.

Biological differences aren't driving heart health during pregnancy as much as the number of years of education.

The findings suggest ways such health disparities might be overcome: “From a public standpoint, we need to improve access to healthy foods, build environments where people can safely walk and play and improve access to preventative healthcare,” said Cameron. “Researchers and policymakers need to partner with communities to make sure these changes are implemented in ways that support their neighborhoods and well-being.”

She believes the next steps are clear. These groups need to “design, implement and test the effectiveness of programs that address these social and environmental factors in improving health before pregnancy.”

The study is published in Circulation: Cardiovascular Quality and Outcomes.