Abstract: The children of expectant mothers who choose cesarean delivery in the absence of a medical indication are at risk for some adverse outcomes. Previous studies have demonstrated that delivery by cesarean section is a risk factor for childhood asthma. There are only limited data on the relationship between mode of delivery and childhood obesity.
The aim of this prospective cohort study was to determine whether a cesarean delivery is a risk factor for childhood obesity. Participants were pregnant women at less than 22 weeks’ gestation enrolled between 1999 and 2002 in Project Viva, a longitudinal prebirth cohort of mother-offspring pairs conducted in eastern Massachusetts. Offspring were followed after birth, and their body composition was measured at 3 years of age. The primary study outcome measures were body mass index (BMI) z score, obesity (BMI ≥95th percentile for age and sex), and skinfold thicknesses (sum of triceps plus subscapular).
Among the 1255 deliveries, 284 (22.6%) were cesarean deliveries. At age 3 years, children delivered by cesarean section were more likely to be obese (15.7% vs 7.5%) than those delivered vaginally. In multivariable regression models, after adjustment for maternal prepregnancy BMI, birth weight, and other covariates, cesarean delivery was associated with a higher risk of obesity (odds ratio, 2.10; 95% confidence interval [CI], 1.36–3.23), higher BMI z score (0.20 U; 95% CI, 0.07–0.33 U), and higher skinfold thicknesses (0.94 mm; 95% CI, 0.36–1.51 mm).
These findings suggest that children delivered by cesarean may be at increased risk of obesity in childhood.