New research suggests that obese, expectant mothers pass on their condition before giving birth.

Do obese mothers automatically produce obese children with metabolic disease?

According to a study being presented today at the American Diabetes Association’s 75th Scientific Sessions, the in utero environment can indeed cultivate a child’s cells to accumulate extra fat.

Researchers say that environment also can produce metabolism differences that can lead to insulin resistance.

Other studies have shown that obesity during pregnancy is a risk factor for increased infant adiposity at birth. Severely overweight women also pass on an increased risk that their children will become obese and have metabolic disease later in life.

In their study, researchers set out to understand how and why that happens.

“One of the questions that needs to be explored is how children of obese mothers may be at risk for becoming obese as a result of factors that occur even before they are born,” said Kristen E. Boyle, Ph.D., an assistant professor at the University of Colorado School of Medicine.

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Boyle’s team examined stem cells from donated umbilical cords. They looked at the cells from babies who had mothers of normal weight during their first prenatal visit and mothers who were obese at the time.

They then grew the cells into fat and muscle cells in a lab. Boyle noted that none of the women gained excessive weight during their pregnancies.

The researchers noticed a 30 percent higher fat content in both types of cells in the children whose mothers were obese. Boyle also noted that when the cells are first harvested, they all have a similar fat content.

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“But as we grow them into fat cells in the lab, the cells from babies of obese mothers accumulate more fat than those from babies of normal weight mothers, which means that there is either a difference in how these cells take fat into the cell, or in how the cells use or store fat inside the cell,” Boyle said.

“At this point, because this is fairly preliminary, we don’t know how these differences in cells grown in the lab correspond to the physiology of these children after birth,” Boyle added. “But it’s clear that there is an inherent propensity toward more fat content in the cells from offspring of obese moms, in culture.”

“We also know that the fat accumulation in these cells corresponded to the baby’s fat mass at birth,” she added.

Next, Boyle and her team will track the children to see if changes occur as they grow. They want to find out how the cells use fat to generate energy, and if that contributes to the higher fat in the cells.

They continue to conduct a full, metabolic assessment of the cells to determine whether the cells in the offspring of obese moms show inflammation, insulin resistance, or other metabolic issues.

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“This type of information hopefully would promote overweight women to strive for an ideal body weight or lose as much weight as possible prior to becoming pregnant,” said Dr. Jerome Tolbert, medical director of outreach at the Friedman Diabetes Institute at Mount Sinai Beth Israel, New York City.

Tolbert said there is more than likely a genetic predisposition that would cause the higher fat content to contribute to the risk of obesity in the developing baby.

“The vast majority of women have no idea that they can pass obesity and the risk of other chronic diseases such as diabetes and heart disease to their developing fetus,” he said.

“These women are also unaware that obesity itself is a disease,” Tolbert added.

Women should pay attention to their weight if they are looking to conceive. Not only can that improve the baby’s health, but it can also make it easier to become pregnant.

“If you are a woman who plans to have kids, you should do everything you can to lower your body fat percentage,” notes Dr. Charlie Seltzer, a weight loss specialist based in Philadelphia. “It will increase the chances of having a healthy baby and decrease your risk of complications from your pregnancy.”

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