Women are already known to be at greater risk of suffering problems during pregnancy and birth if they have children later in life.
Pregnancies among older mothers are associated with higher risk of miscarriage, and conditions such as diabetes and pre-eclampsia, which can threaten the health of mother and baby.
But researchers said the new study of more than 70,000 women suggested that health consequences of later motherhood could occur decades later.
The number of women giving birth over 40 has doubled in 15 years, and risen five-fold since the 1970s, official data for England and Wales shows.
The new study, presented at the American Stroke Association`s International Stroke Conference in Los Angeles, examined data concerning more than 72,000 women.
The researchers compared rates of stroke, heart attack and cardiovascular death among those who gave birth before and after the age of 40.
The chance of the most common type of stroke, caused by a clot, was 58 per cent higher among women who started families later, rising from 2.4 per cent to 3.8 per cent.
Risk of a hemorrhagic stroke, caused by a bleed in the brain – which make up around 1 in 6 strokes - doubled from 0.5 per cent in younger mothers to 1 per cent in older mothers.
Overall, women who got pregnant later in life had a 3.9 per cent risk of cardiovascular death compared to 2.3 per cent of women who became pregnant earlier in life, the study found.
The chance of having a heart attack also rose slightly for women who became pregnant over 40 - from 2.5 per cent to 3 per cent.
Professor Adnan Qureshi, lead researcher and director of the Zeenat Qureshi Stroke Institute in Minnesota, said: "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.
"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."
Last year, official figures showed that for the first time, the number of births involving mothers over the age of 35 has overtaken the number involving those 25 and under.
Overall there were 144,181 babies born in England and Wales to mothers aged 35 or over last year, compared with 138,592 to those under 25.
By contrast, just over 29,000 women over 40 gave birth – twice as many as in 1999. The figures for 2001 include 2,000 births among women over the age of 45.
Childless couples will be able to pay surrogate mothers large sums of money to have babies for them, following a landmark High Court ruling.
Researchers said that risks of older pregnancy – such as heightened blood pressure, a greater chance of diabetes and high cholesterol – explained most of the risks.
But they said they did not explain the higher risk of strokes caused by brain bleeds, calling for more research to be done.
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