Breastfeeding and early childhood caries: a meta-analysis of observational studies.

BACKGROUND AND OBJECTIVES The associations of breastfeeding and early childhood caries (ECC) risk have been evaluated in several epidemiological studies with conflicting results. We performed an update meta-analysis to estimate the association of feeding patterns, breastfeeding durations and ECC risk. METHODS AND STUDY DESIGN Studies were identified through searching Pubmed, Web of Science, and Embase from January 1990 to December 2015. RESULTS Thirty-five studies involving 73,401 participants aged 0-71 months were included. The overall analysis showed children ever breastfed had a reduced risk of ECC compared with those never breastfed (OR=0.77, 95% CI: 0.61-0.97, p=0.026). Subgroup analysis revealed ever breastfeeding significantly reduced ECC risk for the studies with 3-6 years old children (OR=0.70, 95% CI: 0.54-0.90, p=0.005), with sample size >500 subjects (OR=0.63, 95% CI: 0.46-0.87, p=0.004), with Newcastle-Ottawa Scale (NOS) score >=6 (OR=0.66, 95% CI: 0.46-0.94, p=0.023), published after 2010 (OR=0.50, 95% CI: 0.30-0.82, p=0.006), with adjusted OR (OR=0.40, 95% CI: 0.18-0.88, p=0.023). Exclusive breastfeeding did not significantly decrease ECC risk compared with bottle feeding (OR=0.68, 95% CI: 0.35-1.31, p=0.248). The children breastfed >=12 months significantly increased ECC risk compared with those breastfed <12 months (OR=1.86, 95% CI: 1.37-2.52, p<0.001). Whereas, children breastfed >=6 months did not significantly increase ECC risk compared with those breastfed <6 months (OR=1.13, 95% CI: 0.83-1.53, p=0.428). CONCLUSIONS Our analysis suggests ever breastfeeding may protect children from ECC, and breastfeeding duration >=12 months is associated with higher ECC risk. Additional large cohort studies are required to illustrate the relationship in further study.