Cesarean delivery and metabolic risk factors in young adults: A Brazilian birth cohort study

Background: Cesarean delivery (CD) perturbs the assembly of the neonatal gut microbiome and has been associated with child and adult obesity. However, it is still unknown whether CD is associated with metabolic risk factors in young adults. Objective: We investigated the association of CD and metabolic risk factors in young adults in a cohort study who were 23-25 y of age at follow-up. Design: We used data from a cohort study in Ribeirão Preto, Brazil. Baseline data on 6827 singleton pregnancies were collected in 1978-1979, and a sample of 2063 subjects were followed up 23-25 y later (2002-2004). Information on the type of delivery, birth weight, maternal age, parity, maternal schooling, and maternal smoking was obtained after birth. Anthropometric data, biochemical measurements, and information on participant schooling and smoking history were collected at 23-25 y of age. A linear regression was performed to assess the association between CD and biochemical measurements in early adulthood, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results: The mean ± SD age of the subjects was 23.9 ± 0.71 y, and 51.8% of the sample were women. The CD rate was 32.0% and was more common in older (P < 0.001) and more educated mothers (P < 0.001). Compared with vaginal delivery, CD was associated with higher body mass index (BMI) after multivariable adjustment (P < 0.001) but not with glucose, homeostasis model assessment of insulin resistance, the quantitative insulin-sensitivity check index, total cholesterol, LDL cholesterol, HDL cholesterol, or triglycerides (all P > 0.05). Conclusion: In our sample of Brazilian adults, CD was associated with higher BMI but not with other metabolic risk factors.