[Pre-pregnancy BMI, gestational diabetes and different indicators of childhood obesity at the age of four: a prospective cohort study].

Objective

To examine the relationship between pre-pregnancy BMI, gestational diabetes (GDM) and different indicators of childhood obesity at the age of 4.

Methods

Based on Ma'anshan Birth Cohort Study, singleton children who were born in Ma'anshan of Anhui province from October 2013 to April 2015, were followed for 4 years, consecutively. During the first questionnaire survey, data including pre-pregnancy weight, height and socio-demography were collected. During 24-28 week of gestation, 75 g oral glucose tolerance test was conducted for them. Childhood height, weight, waist circumference and body composition were measured at the age of 4. Comparisons between groups were performed using chi-square test, analysis of variance or t-test. The relationship between pre-pregnancy overweight/obesity, GDM and childhood obesity-related characteristics were analyzed by logistic regression model and generalized linear model analysis.

Results

The prevalence rates of overweight and obesity in children at the age of 4 were 13.08% and 6.03%, respectively. After adjustment for characteristics related to mothers and their children, significantly increased risk of obesity (OR=3.27, 95%CI: 2.15-4.98), larger waist circumference (OR=2.32, 95%CI: 1.72-3.14) and higher waist-to-weight ratio (OR=2.29, 95%CI: 1.73-3.02) were seen in the offspring of women with pre-pregnancy overweight/obesity. Body composition (skeletal muscle, body fat, body fat percentage) of the offspring were strongly correlated with pre-pregnancy overweight/obesity of the mothers (P<0.05). Maternal GDM was associated with higher risk of childhood obesity (OR=1.78, 95%CI: 1.14-2.79), on mothers without GDM during pregnancy. However, neither larger waist circumference, or higher waist-to-weight ratio seemed to increase the risk. Moreover, maternal GDM was not associated with body composition measures (skeletal muscle, body fat, body fat percentage).

Conclusion

Pre-pregnancy BMI and maternal GDM were independent risk factors for obesity in 4-year-old children, and pre-pregnancy BMI was correlated with various indicators of body composition in children.