Women who give birth to a baby preterm have a higher risk of suffering from heart disease, according to the findings of a new study.
In findings published in the July issue of the Journal of the American College of Cardiology, researchers warn that preterm delivery should be recognized as a risk for heart disease, which can persist for decades after the birth of a child.
Researchers from the Icahn School of Medicine at Mount Sinai, in New York, conducted a national study involving 2.1 million women who delivered children in Sweden from 1973 to 2015, who were followed up for ischemic heart disease through the end of 2015. The study focused on long-term risks of ischemic heart disease in women by pregnancy duration.
According to the data, nearly 50,000 diagnoses of coronary heart disease occurred among the mothers during that time. However, the researchers found an increased risk among women who gave birth earlier than term. Full term birth is considered birth after 37 weeks.
Women who delivered earlier than 37 weeks had two and half times the risk of having heart disease in the first 10 years after delivering their baby compared to women who delivered full term. Even women who delivered slightly early, from 37 to 38 weeks, had a 47% increased risk of heart disease, compared to women who delivered at term. Women who delivered between 22 to 27 weeks pregnancy had nearly four times the risk of heart disease.
The findings also suggest the increased risk persisted as long as 43 years after the women gave birth. A sub-analysis of more than 1 million sisters who also delivered children at different times showed that the associations were not attributable to shared genetic or environmental factors.
Roughly 10% of infants born in the United States are delivered preterm, or before 37 weeks of pregnancy.
The researchers said preterm delivery should be recognized as a risk factor for heart disease in women. Women who have a history of preterm delivery should be given earlier intervention to help reduce other risk factors for heart disease and other serious side effects, such as increased physical activity, smoking cessation and long-term monitoring for early detection.
“Pre-term delivery was a strong independent risk factor for ischemic heart disease,” the researchers wrote. “This association waned over time but remained substantially elevated up to 40 years later. Pre-term delivery should be recognized as a risk factor for ischemic heart disease in women across the life course.”