Being too small or too large at birth can have many negative effects on children’s health. For example, children who are too large at birth are at increased risk for breathing difficulties, jaundice, and low blood sugar.
Whether an infant is too large or too small has traditionally been measured against averages for entire populations. However, these population-based measures don’t take into account individual factors, such as the mother’s size, and thus may not accurately predict a child’s risk. More recently, scientists have developed customized growth models to account for these individual factors, but these models’ ability to predict health risks has not been tested thoroughly.
Researchers funded through the Pregnancy and Perinatology Branch analyzed data on more than 2,000 infants born to women with mild gestational diabetes meliitus (GDM), a common cause of having a large baby. Their aim was to compare the predictive power of a traditional, population-based growth model with a customized method (known as the Gardosi model) in large infants.
The researchers found that the customized model did not predict the infants’ risk of health problems due to large size any better than the population-based model did. In fact, the study found that neither approach worked very well for identifying which large infants born to women with mild GDM were at risk.
Additional study is needed to determine the best ways to predict, before birth, an infant’s risk of problems related to overgrowth and GDM (PMID: 23147078).