Background/Objectives
The intergenerational association of obesity may be driven by mother-to-newborn transmission of microbiota at birth. Yet Cesarean delivery circumvents newborn acquisition of vaginal microbiota, and has been associated with greater childhood adiposity. Here we examined the independent and joint associations of maternal pre-pregnancy BMI (kg/m2) and delivery mode with childhood overweight or obesity.
Subjects/Methods
We prospectively followed 1,441 racially and ethnically diverse mother-child dyads in the Boston Birth Cohort until age 5y (range 2.0—8.0y). We used logistic regression to examine the independent and joint associations of delivery mode (Cesarean and vaginal delivery) and pre-pregnancy BMI with childhood overweight or obesity (age-sex specific BMI≥85th percentile).
Results
Of 1,441 mothers, 961 delivered vaginally and 480 by Cesarean. Compared to vaginally delivered children, Cesarean delivered children had 1.4 (95% CI 1.1–1.8) times greater odds of becoming overweight or obese in childhood, after adjustment for maternal age at delivery, race/ethnicity, education, air pollution exposure, pre-pregnancy BMI, pregnancy weight gain, and birth weight. Compared to children born vaginally to normal weight mothers, after multivariable adjustment, odds of childhood overweight or obesity were highest in children born by Cesarean delivery to obese mothers (OR 2.8, 95% CI 1.9–4.1), followed by children born by Cesarean delivery to overweight mothers (OR 2.2, 95% CI 1.5–3.2), then children born vaginally to obese mothers (OR 1.8, 95% CI 1.3–2.6), and finally children born vaginally to overweight mothers (OR 1.7, 95% CI, 1.2–2.3).
Conclusions
In our racially and ethnically diverse cohort, Cesarean delivery and pre-pregnancy overweight and obesity were associated with childhood overweight or obesity. Needed now are prospective studies that integrate measures of the maternal and infant microbiome, and other potentially explanatory covariates, to elucidate the mechanisms driving this association and to explore whether exposure to vaginal microbiota in Cesarean delivered newborns may be an innovative strategy to combat the intergenerational cycle of obesity.