The relationship between breastfeeding and motor development in children: a systematic review and meta-analysis

Context The importance and benefits of breastfeeding in children are well recognized, and it may improve motor development. Motor skills are fundamental to childhood development. Although some studies report a positive association between breastfeeding and motor development in children, others have suggested that these differences could be influenced by confounding variables. Objective To estimate the degree to which breastfeeding duration and exclusivity is associated with motor development in children. Thus, a systematic review of the literature and a meta-analysis was conducted. Data Sources MEDLINE (via PubMed), Embase, the Cochrane Database of Systematic Reviews, and the Web of Science databases were systematically searched from inception to June 2021. Data Extraction The most adjusted relative risks (RRs) or odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) reported by included studies were used. The "breastfeeding duration" category defined by each study was used as the reference category. Additionally, subgroup analyses were performed based on the duration of breastfeeding. Data Analysis Eighteen published studies were included in the systematic review and 14 studies in the meta-analysis. The results showed that the effect size (ES) for exclusively breastfed vs never breastfed children was 0.86 (95% CI: 0.32, 1.41, I-2 = 90.3%), and the ES for children breastfed for any length vs never breastfed children was 0.95 (95% CI: 0.80, 1.10, I-2 = 88.0%). The remaining groups studied did not show significant differences in outcomes. Conclusions Although our data suggest that breastfeeding may improve motor development in children, more studies are needed because publication bias has been detected. Nevertheless, our results support the promotion of breastfeeding.