Children born to obese mothers are up to 57 percent more likely to develop cancer, according to new research.
The researchers, who analyzed more than 2 million births and 3,000 cancer cases in Pennsylvania, believe disruptions to insulin levels at crucial points in the fetus's development could set in motion dangerous cell changes that lead to disease years down the line.
The connection is so strong, they said, that it should deter any expectant mothers from fast food and excess sugar, which could derail her insulin control.
'Right now, we don't know of many avoidable risk factors for childhood cancer,' lead author Dr Shaina Stacy, an epidemiologist at the University of Pittsburgh, said.
'My hope is that this study can be, in a way, empowering and also motivating for weight loss.'
Children born to severely obese mothers - with a BMI (body mass index) above 40 - had a 57 percent higher risk of leukemia before the age of five
Her team pored through birth and cancer registry records filed in the state of Pennsylvania between 2003 and 2016.
They found children born to severely obese mothers - with a BMI (body mass index) above 40 - had a 57 percent higher risk of leukemia before the age of five.
This reduces steadily as the mother's BMI falls - meaning cutting down on burgers, cakes and chips during pregnancy may save a child's life.
Dr Stacy said: 'Our intent isn't to shame women or make them feel guilty.
'But instead, we are hoping these findings point to one more reason for weight loss.'