Cesarean section and the risk of overweight in grade 6 children.

UNLABELLED: We examined the relationship between cesarean section (C-section) and the risk of overweight and obesity in children in grade 6 (mean age, 11.92 years; standard deviation = 0.34). Data from phase I through phase III of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were used. Children with complete data from 1991 through 2004 were included in this study (n = 917). Multiple logistic regression analyses were used to adjust for potential confounding and to evaluate the association of C-section and childhood overweight and obesity. Compared to children delivered vaginally, children delivered by C-section had approximately twice the likelihood of being overweight (odds ratio (OR) = 1.86, 95 % confidence interval (CI) = 1.27-2.73) or obese (OR = 1.87, 95 % CI = 1.19-2.95). However, when examined according to sex, males delivered by C-section had an increased risk for being overweight (OR = 1.78, 95 % CI = 1.01-3.12) and obese (OR = 2.58, 95 % CI = 1.36-4.88), while females had an increased risk only for being overweight (OR = 1.99, 95 % CI = 1.17-3.39).

CONCLUSION: C-section was associated with an increased risk of overweight and obesity in children in grade 6, but the relationship differed according to gender. Further longitudinal studies are warranted to examine the long-term effect of delivery mode on the risk of childhood overweight.