Babies born to woman with higher blood sugar levels during pregnancy could be at significantly greater long-term risk of obesity - even more than a decade later, a study has found.

The higher the woman's blood sugar, the greater the risk of her child being obese. The researchers suspect that epigenetic changes are likely to be influencing these long-term outcomes and those changes begin quite early in pregnancy. "The mother's blood sugar level during pregnancy is an independent contributor to the child's weight and risk of being obese later in childhood," said Boyd Metzger, professor at the Northwestern University Feinberg School of Medicine.

In addition, mothers with higher-than-normal blood sugar during pregnancy -- even if not at the level of gestational diabetes -- also were significantly more likely to have developed Type-2 diabetes a decade after pregnancy than their counterparts without high blood sugar, the researchers said, in the paper published in the journal JAMA.

Lowering a mother's blood sugar during her pregnancy reduces the birth weight of the child, as well as the risk of pre-eclampsia -- potentially life-threatening condition in which the mother has high blood pressure that affects her and the baby. If not regulated on time, these can potentially increase the number of women and children at risk of acquiring lifelong chronic medical conditions.

"The results are important because they demonstrate that even women with mild hyperglycemia during pregnancy and their offspring are at risk of harmful maternal and child health outcomes," said coauthor Wendy Brickman, associate professor at Feinberg. "Research is needed to identify interventions that will improve the health outcomes of these women and children," Brickman said

The study evaluated children 10 to 14 years after birth in 10 clinical centers in seven countries: the US, Canada, Israel, the UK, Hong Kong, Thailand and Barbados. 
The study included 4,697 mothers and 4,832 children.