Women who gain weight in pregnancy do not put their children at increased risk of early death in adulthood, a new study suggests.
Research looking at the long-term effects of piling on the pounds during pregnancy found a woman's rate of weight gain was not associated with her adult offspring's risk of death or heart problems.
The University of Aberdeen study found only extreme weight gain was associated with increased risk of cerebrovascular events in the mother's offspring.
In these cases, adult health and lifestyle factors could mitigate the risk.
Previous research has indicated that children born to mothers who were obese or overweight in pregnancy were at greater risk of death or heart-related health problems.
However, the University of Aberdeen team said that until now no study has had adequate follow-up time to assess the effects of weight gain in pregnancy in adult offspring.
The latest study used data from the Aberdeen Children of the 1950s Birth Cohort to follow up 3,781 people whose mothers' weight gain during pregnancy was recorded.
This meant the impact of lifestyle factors in adulthood could also be accounted for.
Dr Sohinee Bhattacharya, who led the study, said: "These findings are quite startling because what they show is that there is basically no relationship between mother's weight gain in pregnancy and heart disease, or premature death in adulthood.
"Only in very extreme cases, where the mother had an exceptionally high weight gain, we found a higher risk of stroke in the adult offspring - however once we took the adults' lifestyle factors into account - such as BMI and smoking status, this difference disappeared.
"So this study provides a very important public health message - you can't do very much about your mother's weight gain in pregnancy, but if you lead a healthy life you can mitigate any effects of this on your risk of having heart disease or dying prematurely.
"For the first time, this large-scale cohort study was able to show that adult health and lifestyle factors - and not early life risk factors - played the most important role in determining cardiovascular mortality and morbidity.
"Modifying these risk factors (obesity, smoking, diabetes) would constitute effective preventive strategy irrespective of maternal or early life factors."
The study was carried out in collaboration with the University of Edinburgh and is published in the journal Heart.
