Pre-pregnancy weight gain can be a major cause for childhood cancer, according to a study. It stated that children born to obese mothers are at higher risk of developing this chronic illness at a very early stage in life.

The research, published in the American Journal of Epidemiology, focused on the various risk factors associated with childhood cancer, such as birth size and maternal obesity. The research team from the University of Pittsburgh Graduate School of Public Health and UPMC Hillman Cancer Center found that pre-pregnancy body mass index (BMI) has a greater role to play in the development of cancer in early childhood.

For the study, the researchers analyzed around two million birth records and nearly 3,000 cancer records registered in the state of Pennsylvania during the years 2003 to 2016. While analyzing the collected information, the research team took into consideration other factors associated with childhood cancer, like maternal age and newborn size.

At the end of the study, the academics found that children born to severely obese mothers – with BMI above 40 – had a 57 percent greater risk of developing leukemia before the age of five. The researchers also found that some of the known risk factors of childhood cancer did not affect the findings. Rather, a mother’s size independently contributed to her child’ risk of developing cancer.

The team said the root cause for increased risk of childhood cancer for kids born to obese mothers could be tied “with insulin levels in the mother’s body during fetal development, or possibly changes to the mother’s DNA expression that are passed to her offspring”.

“Right now, we don’t know of many avoidable risk factors for childhood cancer. My hope is that this study can be, in a way, empowering and also motivating for weight loss,” lead researcher Shaina Stacy, a postdoctoral scholar in the Pitt Public Health Department of Epidemiology and UPMC Hillman Cancer Center, said in a statement.

Stacy also said even smaller amounts of weight loss can reduce the risk of cancer in children. It is mainly because all levels of obesity are not associated with the same risk. Of all the obese women in the study, children born to mothers with higher BMIs had a greater risk of developing cancer.

“We are dealing with an obesity epidemic in this country. From a prevention point-of-view, maintaining a healthy weight is not only good for the mother, but also for the children, too,” Jian-Min Yuan, senior author of the study and co-leader of the cancer epidemiology and prevention program at UPMC Hillman Cancer Center, said.

Obese mother
Cancer risk increases in children born to obese mothers. Pixabay/annaica