Associations of delivery mode and labor with measures of childhood adiposity: findings from Project Viva
Authors: Mueller Noel Theodore , Rifas Sheryl L. , Chavarro Jorge , Oken Emily , Hivert Marie‐France 
Published: November 2023

Background/ObjectivesCesarean vs. vaginal delivery has been associated with higher risk of offspring obesity. The mechanism posited to underlie this association includes differential transfer of bacteria during labor, yet few studies have examined whether the association differs by Cesarean deliveries preceded by labor compared vs. those that are not. The objective of this study was to examine the association of Cesarean delivery—with and without labor—compared to vaginal delivery in relation to measures of adiposity in offspring in childhood.MethodsWe ascertained information on delivery mode (Cesarean or vaginal) and labor (yes or no) from medical records in 1443 mother‐child dyads from the Project Viva cohort with complete pre‐birth data and anthropometric measures from at least 1 follow‐up visit (3334 total observations) in early childhood (median age 3.2y), mid‐childhood (median 7.7y), or early teen (median 13.0y). Child adiposity outcomes were CDC age‐ and sex‐specific BMI z‐scores, sum of subscapular (SS) and triceps (TR) skinfold thicknesses (mm), and waist circumference (cm). We used generalized estimating equation models with auto regressive correlation structure adjusted for maternal age, education, race/ethnicity, pre‐pregnancy BMI, and child sex and age at outcome. We evaluated effect modification by maternal pre‐pregnancy BMI (<25 vs. 325 kg/m2) and child sex.ResultsOf the 333 (23%) women who delivered via Cesarean, 229 (69%) had labor, 99 (30%) had no labor and 5 (1%) had unknown labor status. Compared to vaginally delivered children, Cesarean delivered children had higher BMI‐z (adjusted b = 0.17; 95% CI 0.06, 0.28); and marginally higher sum of skinfolds (adjusted b = 0.58 mm; 95% CI −0.42, 1.58) and waist circumference (adjusted b = 0.58 cm; 95% CI −0.29, 1.46). Associations for skinfolds and waist circumference appeared stronger among Cesarean deliveries not preceded by labor compared with those that were (Table). Associations were similar after additional adjustment for gestational weight gain and birth weight for gestational age; did not change over time; and were not modified by pre‐pregnancy BMI or child sex (interaction p‐values >0.05).ConclusionCesarean delivery was associated with higher childhood measures of adiposity, particularly BMI. Associations with skinfolds and waist circumference, more direct measures of adiposity, appeared stronger among planned Cesarean deliveries without labor, suggesting exposure to labor may partly modify the association of delivery mode with offspring adiposity.

Associations of delivery mode and adiposity in children (between age 2.8 and 16.6y) from Project Viva.

Adjusted* β (95% CI) compared with vaginal delivery (reference)

BMI score
z−
SS+TR, mm
Waist circumference, cm

Any Cesarean
0.17 (0.06, 0.28)
0.58 (−0.42, 1.58)
0.58 (−0.29, 1.46)

Cesarean w/labor
0.17 (0.04, 0.30)
0.23 (−0.87, 1.32)
0.33 (−0.64, 1.29)

Cesarean no labor
0.17 (−0.03, 0.37)
1.43 (−0.47, 3.33)
1.18 (−0.52, 2.87)

We used generalized estimating equations with auto regressive correlation structure to examine 3334 observations in 1443 children.
Multivariable model is adjusted for maternal age, pre‐pregnancy BMI, education, race/ethnicity and child age and sex.