Associations between a maternal healthy lifestyle score and adverse offspring birth outcomes and childhood obesity in the Lifeways Cross-Generation Cohort Study.

BACKGROUND/OBJECTIVES: Maternal adherence to healthy lifestyle behaviors during pregnancy has been associated with reduced risk of obesity in the offspring. Our objective is to examine associations between a composite healthy lifestyle score (HLS) in expectant mothers and adverse offspring birth outcomes and childhood obesity. SUBJECTS/METHODS: The Lifeways Study comprises 665 mother-child pairs. A composite HLS (scored 0-5) based on high dietary quality (top 40% of the Healthy Eating Index (HEI)-2015), moderate to vigorous physical activity (MVPA), healthy pre-pregnancy BMI (18.5-24.9 kg/m2), never smoker, and no/moderate alcohol intake was calculated. Birth outcomes were abstracted from hospital records. Offspring waist circumference (WC) and BMI was determined at age 5 and 9. Logistic regression tested HLS associations with offspring outcomes. RESULTS: Offspring birth weight, length, and head circumference were positively associated with the maternal HLS (p < 0.001), whereas child BMI and incidence of overweight/obesity at age 5 and 9 were negatively associated (p < 0.05). In multivariable models, a lower maternal HLS was associated with increased risk of low birth weight (LBW) (P trend = 0.04) and lower likelihood of macrosomia (P trend = 0.03). Examined individually, poor maternal dietary quality, smoking, and alcohol intake were associated with higher risk of LBW (p < 0.04). Likelihood of macrosomia and combined overweight/obesity at age 5 and 9 years were greater among mothers with a pre-pregnancy BMI in the range with obesity (p < 0.04). Smoking during pregnancy was also linked to greater risk of childhood overweight/obesity (OR:1.91, 95% CI:1.01-3.61, p = 0.04 at age 5 and OR: 2.14, 95% CI:1.01-4.11, p = 0.03 at age 9). CONCLUSIONS: Our findings suggest that maternal adherence to a healthy lifestyle during pregnancy, in particular having a good quality diet, not smoking, and no/low alcohol intake in combination with a healthy pre-pregnancy BMI, is associated with reduced risk of adverse offspring birth outcomes and childhood obesity.