18/02/2016 00:01 GMT | Updated 17/02/2017 05:12 GMT

Heart Attack, Stroke Risk 'Higher Among Women Who Give Birth After 40'

Women who delay motherhood until they are 40 or older are more likely to have a heart attack or a stroke in later life than women who have children at a younger age, new research suggests.

The study, presented at the American Stroke Association's International Stroke Conference in Los Angeles, examined data concerning more than 72,000 women, 3,300 of them reported that they became pregnant late in life.

The researchers compared their rates of stroke, heart attack and cardiovascular death over 12 years of follow up with women who were pregnant at a younger age.

They found that 2.4% of women who were pregnant at a younger age were at risk of ischemic stroke compared to 3.8% of women who got pregnant over the age of 40.

Risk of a hemorrhagic stroke rose from 0.5% in younger mothers to 1% in older mothers. The chance of having a heart attack also rose slightly for women who became pregnant over 40 - from 2.5%  to 3%.

Meanwhile women who got pregnant later in life had a 3.9% risk of cardiovascular death compared to 2.3% of women who became pregnant earlier in life.

"We already knew that older women were more likely than younger women to experience health problems during their pregnancy," said Professor Adnan Qureshi, lead researcher and director of the Zeenat Qureshi Stroke Institute in Minnesota.

"Now, we know that the consequences of that later pregnancy stretch years into the future.

"Women with a late pregnancy need to be aware of their increased risk and take steps to improve their cardiovascular health. And their doctors need to remain vigilant years later in monitoring these women's risk factors through physical examination and, perhaps more tests and earlier interventions to prevent stroke and other cardiovascular events."

In 2014, 4% of newborns in England and Wales were born to mothers aged over 40, according to Office for National Statistics figures.