Cesarean delivery and risk of childhood obesity.

OBJECTIVE: To investigate whether birth by cesarean delivery rather than vaginal delivery is a risk factor for later childhood obesity.

STUDY DESIGN: Healthy, full-term infants were recruited. Overweight and obesity were defined using measured weight and height according to World Health Organization reference data. Associations between cesarean delivery and being overweight or obese were investigated at age 2, 6, and 10 years (n = 1734, 1244, and 1170, respectively) by multivariate logistic regression models adjusted for socioeconomic status, child characteristics, and maternal prepregnancy characteristics.

RESULTS: Mothers who gave birth by cesarean delivery (∼17%) had a higher mean prepregnancy body mass index (23.7 kg/m(2) vs 22.5 kg/m(2)), greater mean gestational weight gain (15.3 kg vs 14.5 kg), and shorter mean duration of exclusive breastfeeding (3.4 months vs 3.8 months) compared with those who delivered vaginally. The proportion of obese children was greater in the cesarean delivery group compared with the vaginal delivery group at age 2 years (13.6% vs 8.3%), but not at older ages. Regression analyses revealed a greater likelihood of obesity at age 2 years in the cesarean delivery group compared with the vaginal delivery group at age 2 years (aOR, 1.68; 95% CI, 1.10-2.58), but not at age 6 years (aOR, 1.49; 95% CI, 0.55-4.05) or age 10 years (aOR, 1.16; 95% CI, 0.59-2.29).

CONCLUSION: Cesarean delivery may increase the risk of obesity in early childhood. Our results do not support the hypothesis that an increasing rate of cesarean delivery contributes to obesity in childhood.