FRIDAY, March 13, 2015 (HealthDay News) -- Being overweight or obese before pregnancy, or gaining too much weight during pregnancy, may put children at increased risk for obesity, a new study says.
"Some weight gain during pregnancy is normal, but women need to know that gaining too much weight can put their child at risk for being obese in childhood and as they get older, which places them at higher risk for future chronic disease," said study author Elizabeth Widen. She is a postdoctoral fellow at Columbia University Mailman School of Public Health in New York City.
"Because pregnancy weight gain has lasting implications for childhood health, we need to determine how to support women to gain a healthy amount of weight in pregnancy," Widen said in a university news release.
The study included 727 black and Dominican mothers in northern Manhattan and the South Bronx in New York City. Before pregnancy, 45 percent were overweight or obese, and 64 percent of them gained more than the recommended amount of weight during pregnancy.
The study found that 22 percent of the children born to these women were obese by age 7. Moreover, on average, 24 percent of their body mass was fat.
The researchers determined that children born to mothers who had excessive weight gain during pregnancy were more likely to be obese. In addition, children born to women who were overweight or obese before pregnancy had a 300 percent increased risk of obesity.
The study was published online in the journal Maternal & Child Nutrition.
The U.S. Institute of Medicine Guidelines recommends that pregnant women within a normal weight range gain a total of 25-35 pounds, with approximately 1 pound a week in the second and third trimesters.
"This is the first study to evaluate the long-term effects of gestational weight gain in a contemporary low-income multi-ethnic urban population, characterized by a high risk of obesity," said Widen.
While the study doesn't prove that the children became obese because their moms were overweight in pregnancy, it does suggest an association.
Dr. Andrew Rundle, an associate professor of epidemiology at Columbia, said the findings are cause for concern.
"A stronger focus on helping pregnant women meet the Institute of Medicine's targets for healthy weight gain during pregnancy is needed," he added.
The U.S. Office of Disease Prevention and Health Promotion outlines how to keep children at a healthy weight.