All major pregnancy complications, including pre-eclampsia and pre-term birth, are associated with an increased heart disease risk for decades after delivery, research suggests.
A study of data from more than two million women with no history of heart disease who gave birth for the first time between 1973 and 2015 showed that preterm delivery, having a baby small for gestational age, pre-eclampsia, other hypertensive disorders of pregnancy, and gestational diabetes all increase the risk of ischemic heart disease for up to 46 years.
These pregnancy complications should be considered as life-long risk factors and women should be offered appropriate care to prevent heart disease developing, the researchers concluded in the paper in the BMJ.
The researchers found that 3.8% of the cohort were subsequently diagnosed with heart disease, at an average age of 58 years.
After adjusting for other factors that may have influenced the results such as smoking and BMI, they found that in the in the 10 years after delivery, relative rates of ischemic heart disease were increased twofold in women with other hypertensive disorders of pregnancy, 1.7-fold in those with preterm delivery, 1.5-fold in those with pre-eclampsia, 1.3-fold in those with gestational diabetes, and 1.1-fold in those who delivered a small for gestational age infant.
And the risk increased where several adverse pregnancy outcomes were present with a ten-year increased risk of 1.3-fold, 1.8-fold, and 2.3-fold for one, two or three of the complications respectively.
While most relative rates did fall over time, they remained significantly higher even three or four decades after delivery and could only be partially explained by shared genetic or environmental factors within families, the researchers said.
Some other studies had also pointed to adverse pregnancy outcomes and higher future risk of cardiovascular disease but not many have looked at multiple factors at once and in such a large cohort.
Yet complications in pregnancy remain an under-recognised factor in future cardiovascular risk, the researchers said.
It is estimated that up to a third of pregnancies could be impacted by at least one adverse pregnancy outcome.
‘All major adverse pregnancy outcomes should be recognized as lifelong risk factors for ischemic heart disease.
‘Women with adverse pregnancy outcomes should be considered for early preventive evaluation and long-term risk reduction to help prevent the development of ischemic heart disease,’ the US and Swedish team concluded.
Ruth Goss, senior cardiac nurse at the British Heart Foundation, said: ‘Studies like these are really important in highlighting women-specific risks of heart disease. Coronary heart disease kills more than twice as many women as breast cancer in the UK every year, and is the single biggest killer of women worldwide.
‘If you’re aged between 40 and 74, or have a history of heart disease in your family, it’s important to understand your potential risk of a heart attack. The NHS health check in England offers a free check-up of your overall health, including blood pressure, high cholesterol and blood glucose check, and can help you take the necessary actions to reduce your risk of developing heart disease.’