Mixed

Maternal overweight/obesity increases the risk of childhood overweight/obesity, with the magnitude of risk being significantly higher for cesarean-delivered infants compared to vaginally delivered infants, mediated sequentially by birth mode and infant gut microbiota (specifically Firmicutes richness and Lachnospiraceae abundance).

For mothers with overweight or obesity, be aware that both vaginal and cesarean delivery carry an increased risk of childhood overweight compared to normal-weight mothers, with cesarean delivery showing a higher risk. This risk is partly mediated by the infant's gut microbiota, specifically the abundance of Lachnospiraceae. While birth mode cannot be changed post-delivery, understanding this link highlights the importance of early gut health. Postnatal factors such as breastfeeding, diet, and antibiotic exposure also shape the microbiome and may offer opportunities to mitigate risk.