Women who become pregnant when they are aged 40 or older may have an increased risk of suffering a heart attack or stroke later in life, a new study has found.

"We already knew that older women were more likely than younger women to experience health problems during their pregnancy. Now, we know that the consequences of that later pregnancy stretch years into the future," the researchers commented.

They looked at over 72,200 women aged between 50 and 79. Among these, just over 3,300 had become pregnant at a later age. Their rates of cardiovascular disease, heart attack and stroke were compared over a 12-year period with those who had become pregnant at a younger age.

The study found that compared to women who got pregnant at a younger age, those who got pregnant at the age of 40 or above had an increased risk of suffering an ischaemic stroke, which is the most common type of stroke, and a haemorrhagic stroke, which results in a bleed on the brain.

They also had an increased risk of suffering a heart attack and were more likely to die from all forms of cardiovascular disease.

The researchers from Germany and the US noted that until now, the age of a woman during her last pregnancy has not been considered a risk factor for stroke and heart attack.

"However, 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," the team said.

Details of these findings were presented at the American Stroke Association's International Stroke Conference 2016 in Los Angeles.