Heart attack risk increasing for pregnant women, study says

July 18 (UPI) -- The risk of a woman having a heart attack while pregnant, giving birth or up to two months after delivery has risen 25 percent over 12 years, a study reveals.

New York University School of Medicine researchers analyzed medical records for more than 49 million births between 2002 to 2014 collected by the U.S. Agency for Healthcare Research and Quality's National Inpatient Survey, finding that heart attacks occurred in 1 of every 12,400 hospitalizations.

The study results were published Wednesday in the journal Mayo Clinic Proceedings.

"Our analysis, the largest review in a decade, serves as an important reminder of how stressful pregnancy can be on the female body and heart, causing a lot of physiological changes, and potentially unmasking risk factors that can lead to heart attack," study senior investigator Dr. Sripal Bangalore, an interventional cardiologist at NYU, said in a press release.

The death rate remains high, and unchanged, at 4.5 percent, the researchers reported.

Rates for myocardial infarction, or heart attack, increased from 7.1 for every 100,000 pregnancies in 2002 to 9.5 for every 100,000 in 2014.

Researchers found that 1,061 heart attacks happened during labor and delivery among the nearly 50,000 births recorded at hospitals among women 18 and older. Another 922 women were hospitalized for myocardial infarction before birth and 2,390 heart attacks occurred after birth.

Researchers believe the risk has increased because more women are having children later in life. In addition, they say more pregnant women are obese, have diabetes or both.

Heart attacks are easier to detect than a decade ago because early protein markers of related heart cell damage are improved and more widely available, the researchers said. But the numbers have increased despite improved drug-coated stents and blood-thinning medications to prevent heart-vessel blockages.

"Our findings highlight the importance to women considering pregnancy to know their risk factors for heart disease beforehand," said study first author Nathaniel R. Smilowitz, who is also an interventional cardiologist. "These patients should work out a plan with their physicians to monitor and control risk factors during pregnancy so that they can minimize their risk."