Children born to obese and overweight mothers are a third more likely to die early of heart disease, according to a new Scottish study.
The analysis of 28,540 women whose weight was recorded at their first antenatal check-up and their 37,709 children showed a 35% higher risk of dying before the age of 55 in adults whose mothers were obese in pregnancy.
Major public health concern
With one woman in five in the UK is obese at their antenatal booking appointment the authors say their findings are of "major public health concern".
Study lead Prof Rebecca Reynolds, of the University of Edinburgh, said: "As obesity among pregnant women is rising, along with levels of obesity in the general population, our findings are of major public health concern.
"This study highlights the need for more research to better understand and prevent the impact of obesity during pregnancy for offspring in later life and the biological processes at work."
There were 6,551 premature deaths from any cause in the study and heart disease was the leading contributor. One in five mothers had a body mass index (BMI) between 25 and 29.9 and 4% were obese with a BMI above 30.
Start pregnancy at a normal weight
The risk of premature death was 35% higher among people born to obese mothers compared with those whose mothers had had normal weight in pregnancy.
This was after adjusting the results for factors such as the mother's age at delivery, social class and infant birthweight.
The results also revealed that children born to obese mothers went on to be at 42% increased risk of being treated in hospital for a heart attack, stroke or angina.
The Royal College of Midwives said it was important for women to start their pregnancy at a normal weight.
But Louise Silverton, RCM director for midwifery, said not all pregnancies are planned and midwives work hard to support women avoid excess weight gain and lose weight sensibly after birth.