Maternal Obesity, Diabetes during Pregnancy, Gestational Weight Gain, Breastfeeding, and Child’s BMI Growth Trajectory from Ages 2 to 6 Years

Limited studies have evaluated the interplay among maternal obesity, maternal diabetes including preexisting type 1 (T1D), type 2 (T2D) or gestational diabetes mellitus (GDM), excessive gestational weight gain (EGWG), and breast feeding (BF) in association with childhood growth trajectory. Here we assessed their associations with child’s BMI trajectory from ages 2 to 6 years. Data included 71,892 singleton children born at 28-44 gestational weeks in 2007-2011 at Kaiser Permanente Southern California hospitals who had at least 5 BMI measurements between ages 2 to 6. First, BMI trajectory patterns for these children were identified using group-based trajectory modeling method. Second, the relationships between maternal exposures and growth trajectory groups were evaluated using multinomial logistic regression adjusting for maternal age at delivery, race/ethnicity, education, and child’s sex. Three distinct BMI trajectory groups were identified: group 1 (59% of the cohort) had stable low BMI over time, group 2 (35% of the cohort) had stable median BMI over time, and group 3 (6% of the cohort) had high and increasing BMI over time. Relative to group 1, the adjusted odds ratio (OR[95% CI]) of being in group 3 associated with maternal exposures were 8.0 [7.3-8.8] for pre-pregnancy obesity, 2.8 [2.6-3.1] for pre-pregnancy overweight, 2.1 [1.2-3.8] for T1D, 1.7 [1.5-2.0] for T2D, 1.2 [1.1-1.4] for GDM, 1.5 [1.4-1.6] for EGWG, and 1.3 [1.2-1.4] for BF<6 months after adjusting for each other. ORs of being in group 2 were much smaller and were insignificant for T1D and GDM. Further adjustment for birth weight and gestational age at delivery had a small effect on the OR estimates but did not change the conclusion. Thus, among the four exposures, high and increasing BMI trajectory in offspring from age 2 to 6 years was strongly associated with maternal obesity and overweight; modestly with maternal T1D, T2D, and EGWG; and slightly with BF<6 months and GDM.