Cesarean Delivery and Body Mass Index at 6 Months and Into Childhood.

BACKGROUND AND OBJECTIVES

The prevalence of cesarean delivery (CD) is rising worldwide, and so is childhood obesity. Studies have shown associations between these factors. We examined the development of BMI from birth through childhood to determine whether CDs were associated with differences in growth and obesity.

METHODS

Term children from the birth cohorts Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) and COPSAC were included. Height, length, and weight measurements were collected prospectively until 5 years in COPSAC and until 13 years in COPSAC. Dual-energy x-ray absorptiometry (DXA) scans were performed at 3.5 and 7 years. Information on relevant covariates were verified during clinical visits. Analyses were adjusted for covariates associating with CD.

RESULTS

In COPSAC, 20% ( = 138/673) of the children were delivered by CD; 49% were girls. In COPSAC, 19% ( = 76/393) were delivered by CD; 51% were girls. Children delivered by CD had a higher mean BMI at 6 months compared with those delivered vaginally: COPSAC β-coefficient, .41 (95% confidence interval [CI], .12 to .69), = .01; COPSAC β-coefficient, .16 (95% CI, -.11 to .68), = .16; and meta-analysis β-coefficient, .37 (95% CI, .14 to .60), = .002. There were no differences in BMI trajectory between the 2 groups by 5 and 13 years, nor cross-sectional BMI at 5 and 13 years, nor in fat percentages from DXA scans.

CONCLUSIONS

Children delivered by CD had a higher BMI at 6 months of age, but this difference did not track into later childhood. Our study does not support the hypothesis that CD leads to later overweight.