Association between caesarean section and childhood obesity: a systematic review and meta‐analysis

Abstract

Birth by caesarean section has been recently implicated in the aetiology of childhood obesity, but studies examining the association have varied with regard to their settings, designs, and adjustment for potential confounders. We conducted a systematic review and meta-analysis to summarize the available evidence and to explore study characteristics as sources of heterogeneity. A search of Medline, EMBASE, and Web of Science identified 28 studies. Random effects meta-analysis was used to calculate pooled risk ratios (RR) with 95% confidence intervals (CI). Caesarean section had a RR of 1.34 (CI 1.18-1.51) for obesity in the child compared with vaginal birth. The RR was lower for studies that adjusted for maternal pre-pregnancy weight than for studies that did not (1.29, CI 1.16-1.44 vs. 1.55, CI 1.11-2.17). Studies that examined multiple early life factors reported lower RRs than studies that specifically examined caesarean section (1.39, CI 1.23-1.57 vs. 1.23, CI 0.97-1.56). Effect estimates did not vary by child's age at obesity assessment, study design or country income. Children born by caesarean section are at higher risk of developing obesity in childhood. Findings are limited by a moderate heterogeneity among studies and the potential for residual confounding and publication bias.

The Bacterial Microbiome and Virome Milestones of Infant Development

“…[ 1 _ T D $ D I F F ] By contrast, infants born by C-section have a gut microbiome most similar to their mother's skin bacterial microbiome. Interestingly, this altered colonization pattern seen in babies delivered via C-section persists to at least 1 year of age [12,13] and has been hypothesized to be responsible for the increased risk of obesity [14] and asthma [15] seen in children delivered by C-section. A pilot study to expose infants delivered by C-section to maternal vaginal fluids [16] demonstrated that vaginal microbes could be partially restored at birth in C-sectiondelivered babies.…”

Cesarean section may increase the risk of both overweight and obesity in preschool children

“…Regarding the association between CS and childhood obesity, recent studies including a meta-analysis observed that cesarean section is associated with increased risk of childhood overweight/obesity [8, 9]. In contrast, few studies reported no significant association between CS and overweight/obesity in children at the age of 6 or 7 [10, 11].…”

Caesarean section is associated with offspring obesity in childhood and young adulthood

“…The study adds to the now ∼80 studies and several systematic reviews that examined the association between CS and offspring obesity 1 2. The study by Yuan and colleagues is one of the largest and stands out in its ability to thoroughly adjust for potential confounders.…”

“…Maternal pre-pregnancy weight confounds this association, as obesity in the mother is associated with CS and offspring obesity. Not all previous studies were able to adjust for maternal pre-pregnancy weight, but a recent systematic review showed that in studies that were able to adjust for this confounder, there remained a statistically significant association of CS with obesity in the offspring 1. The large prospective cohort study by Yuan et al aimed to examine the association between CS and offspring obesity adjusting for all potential confounders.…”