Unexpected Trends in Infant Growth Following Exposure to Gestational Diabetes

The findings, published today in the American Journal of Clinical Nutrition, challenge existing assumptions about the obesity risk in these infants, revealing that they actually gain fat at a slower rate compared to babies not exposed to GDM during their first year. This indicates that early growth in babies may be more adaptable and self-regulating than previously believed, suggesting that those whose mothers had GDM might not inherently be at risk of obesity but may benefit from extra monitoring to promote healthy growth.

“It is common to assume that infants exposed to gestational diabetes automatically face a higher risk for childhood obesity, but our research depicts a more nuanced scenario,” stated Elizabeth Widen, the study’s lead author and an assistant professor of nutritional sciences at UT Austin. “While these infants may be born with a higher amount of body fat, many appear to self-regulate over time.”

Infants born from mothers with GDM exhibited higher body fat levels at birth yet demonstrated a slower increase in fat during their first year, indicating a more dynamic early-life growth pattern that prior research may have overlooked.

GDM affects around 8.3% of pregnancies in the U.S., and this figure has significantly escalated over the last 20 years. Mothers with GDM are at a heightened risk for pregnancy complications and are more likely to develop Type 2 diabetes later in life. Babies exposed to Type 2 diabetes typically have higher birth weights, an increased percentage of body fat, and elevated body mass indexes. Earlier studies have identified a greater likelihood of developing Type 2 diabetes and obesity later for those exposed to GDM while in utero.

The research tracked 198 infants, half of whom were exposed to GDM before birth. Data was gathered between 1996 and 2006, mainly involving participants recruited prior to the common practice of treating GDM with medications like metformin or insulin to manage blood sugar levels.

“These findings align with data from the Maternal Fetal Medicine Units Network regarding mild GDM treatment in pregnancy, which indicated no decrease in the rates of childhood obesity or metabolic issues between ages 5 to 10 among children of treated GDM mothers compared to controls,” noted Patrick Catalano, a professor of reproductive endocrinology at Harvard Medical School who oversaw the data collection.

Researchers evaluated each infant’s weight, length, and body fat at birth, followed by numerous measurements over their first year. To analyze growth patterns, the team utilized advanced statistical methods, revealing three distinct trajectories of growth.

“Interestingly, infants exposed to GDM were statistically more likely to experience slower increases in body fat, while gaining lean body mass at a comparable rate to infants of mothers without GDM. This phenomenon, termed catch-down growth, typically occurs in heavier babies who later adjust to average growth patterns,” explained Widen.

The analysis found that GDM-exposed infants were significantly more inclined to display slow growth in fat mass and percentage of body fat, as well as being more likely to fall into the category with the slowest increases in BMI, or even experiencing a decrease in BMI.

“Previous research has largely overlooked this critical first year of life using the precise body fat measures we employed in our study,” remarked Rachel Rickman, the lead author and a former doctoral student of Widen. “The results are indeed significant and prompt a multitude of new questions.”

Marcela R. Abrego and Saralyn F. Foster from UT Austin, Amy R. Nichols from the University of California, Davis, and Charlotte E. Lane from Food Security Evidence Brokerage also contributed to this paper. The research received funding from the National Institute of Child Health and Human Development, as well as the General Clinical Research Center.