Because heart disease accounts for 26.5 percent of pregnancy-related deaths, the American College of Obstetricians and Gynecologists (ACOG) has created new guidelines on screening, diagnosis, and management of heart disease.

During pregnancy, the cardiovascular system undergoes major changes to sustain “tremendous increases in blood volume,” said Dr. James Martin, chairman of ACOG’s pregnancy and heart disease task force. “That’s why it is critical to identify the risk factors beforehand.”

A heart muscle disease called peripartum cardiomyopathy is the leading cause of death in expectant mothers, accounting for 23 percent of deaths late in pregnancy.

Common risk factors for maternal death due to heart disease include age, high blood pressure during pregnancy, and obesity.

But the leading factor is race. The risk of death from heart disease is 3.4 times higher among black women than white women.

All pregnant women and new mothers should be assessed for heart disease using a tool known as the Cardiovascular Disease Toolkit algorithm, which was developed from research that found about 9 in 10 pregnant women and new moms who died of heart disease would have been identified as high risk had this new screening algorithm been used.