Association between caesarean section delivery and obesity in childhood: a longitudinal cohort study in Ireland.

OBJECTIVES

To investigate the association between caesarean section (CS) birth and body fat percentage (BF%), body mass index (BMI) and being overweight or obese in early childhood.

DESIGN

Prospective longitudinal cohort study.

SETTING

Babies After Screening for Pregnancy Endpoints: Evaluating the Longitudinal Impact on Neurological and Nutritional Endpoints cohort.

PARTICIPANTS

Infants born to mothers recruited from the Screening for Pregnancy Endpoints study, Cork University Maternity Hospital between November 2007 and February 2011.

OUTCOME MEASURE

Overweight or obese defined according to the International Obesity Task Force criteria.

RESULTS

Of the 1305 infants, 362 (27.8%) were delivered by CS. On regression analysis, BF% at 2 months did not differ significantly by delivery mode. Infants born by CS had a higher mean BMI at 6 months compared with those born vaginally (adjusted mean difference=0.24; 95% CI 0.06 to 0.41, p value=0.009). At 2 years, no difference was seen across the exposure groups in the risk of being overweight or obese. At 5 years, the association between prelabour CS and the risk of overweight or obesity was not statistically significant (adjusted relative risk ratio, aRRR=1.37; 95% CI 0.69 to 2.69) and the association remained statistically nonsignificant when children who were macrosomic at birth were excluded from the model (aRRR=0.86; 95% CI 0.36 to 2.08).

CONCLUSION

At 6 months of age, children born by CS had a significantly higher BMI but this did not persist into future childhood. There was no evidence to support an association between mode of delivery and long-term risk of obesity in the child.