Today, American infants up to 6 months of age are 59 percent more likely to be overweight than were babies born 20 years ago, a recent study found.
And though chubby babies might be viewed as cute and healthy, parents need to think about preventing obesity at the earliest stages of life, health experts are warning. That means paying attention not only to infant weights, but also to a mother's weight before conception and her weight gain during pregnancy.
"A mother's weight gain during pregnancy, particularly gaining more than is recommended, is associated with an increased likelihood of childhood obesity," said Dr. Christine M. Olson, professor of community nutrition at Cornell University, in Ithaca, N.Y.
Olson's own research found that to be true. She followed 208 mother-child pairs and found that excess weight gained during pregnancy -- meaning more than 25 to 35 pounds for a woman who began pregnancy at a normal weight -- increased the risk of her child being overweight at 3 years of age. She defined overweight at age 3 as weighing more than 85 percent of children at that age.
About 40 percent of the children born to mothers who were overweight or obese in early pregnancy were overweight by age 3, whereas just 24 percent of those born to mothers whose pregnancy weight was normal or below normal were overweight by age 3.
The impact was greater among women who were overweight or obese before they became pregnant.
The associations ring true, said Dr. Frank R. Greer, a professor of pediatrics at the University of Wisconsin School of Medicine and Public Health and chairman of the nutrition committee for the American Academy of Pediatrics.
"Certainly, overweight mothers are at risk for having overweight infants," he said. "Mothers who have gestational diabetes [diagnosed during pregnancy] are also at greater risk." And if the child's father is overweight, he said, that can also help predict whether the baby will be overweight.
But, Greer added, it's not a simple issue.
"Predicting obesity in the first year of life is problematic," Greer said. "Obviously, you can pick out the infants at risk by looking at their birth weight and looking at their parents. However, pediatricians are reluctant to do this at the well-baby visit before the infant is approaching the 85th percentile for weight," generally considered the threshold for being classified as overweight.
What to do? Greer and Olson have a number of suggestions.
Besides getting down to a healthy weight before becoming pregnant, women should follow the weight-gain guidelines during pregnancy, they said. That means 25 to 35 pounds for normal-weight women, more for underweight and less for overweight. Ask your doctor what's best for you.
Only about 40 percent of women stay within the recommended weight-gain guidelines, Olson has found.
Breast-feeding for the first four to six months can help reduce the chances that a child will become overweight, Olson and Greer agreed. But exclusive breast-feeding for that long can be a challenge, Olson said, especially if a woman is returning to work.
Olson advised women to research their rights. A New York law, for instance, mandates breaks during work for women to pump milk, Olson said. Breast-feeding mothers might also want to ask their supervisors for support and input on how to better mesh breast-feeding and working.