The Effects of Race and Ethnicity on the Risk of Large-for-Gestational-Age Newborns in Women Without Gestational Diabetes by Prepregnancy Body Mass Index Categories

Objectives Children born large for gestational age (LGA) are at risk of numerous adverse outcomes. While the racial/ethnic disparity in LGA risk has been studied among women with Gestational Diabetes Mellitus (GDM), the independent effect of race on LGA risk by maternal prepregnancy BMI is still unclear among women without GDM. Therefore, the objective of this study was to assess the association between maternal race/ethnicity and LGA among women without GDM. Methods This was a population-based cohort study of 2,842,278 singleton births using 2012 U.S. Natality data. We conducted bivariate and multivariate logistic regression analyses to assess the association between race and LGA. Due to effect modification by maternal prepregnancy BMI, we stratified our analysis by four BMI subgroups. Results The prevalence of LGA was similar across the different racial/ethnic groups at about 9%, but non-Hispanic Asian Americans had slightly higher prevalence of 11%. After controlling for potential confounders, minority women had higher odds of birthing LGA babies compared to non-Hispanic white women. Non-Hispanic Asian Americans had the highest odds of LGA babies across all BMI categories: underweight (aOR = 2.67; 95% CI: 2.24, 3.05); normal weight (aOR = 2.53; 2.43, 2.62); overweight (aOR = 2.45; 2.32, 2.60) and obese (aOR = 2.05; 1.91, 2.20). Conclusions for practice Racial/ethnic disparities exist in LGA odds, particularly among women with underweight or normal prepregnancy BMI. Most minorities had higher LGA odds than non-Hispanic white women regardless of prepregnancy BMI category. These racial/ethnic disparities should inform public health policies and interventions to address this problem.