Abstract
BACKGROUND: Breastfeeding (BF) has been reported to be beneficial for both mothers and their offspring, but the evidence for these associations has not been systematically evaluated. OBJECTIVES: This umbrella review aims to assess the credibility of existing evidence regarding the associations between BF and health outcomes in mothers and offspring. METHODS: For each health outcome, evidence levels were determined using reanalyzed random-effects estimates, between-study heterogeneity, 95% predictive intervals, publication bias, small-study effects, and excess significance bias. Methodological quality was assessed by A Measurement Tool to Assess Systematic Reviews 2, and evidence credibility was graded with the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). RESULTS: Overall, 192 meta-analyses from 62 articles were included. Among maternal outcomes, 3 meta-analyses (3/65, 4.6%) were considered to provide convincing evidence that BF reduced risks of ovarian cancer [odds ratio (OR) range: 0.70-0.78] and hypertension (OR range: 0.89-0.93). For short-term offspring outcomes, 5 meta-analyses (5/114, 4.4%) were considered to provide convincing evidence that exclusive BF or ever BF was associated with lower risks of sudden infant death syndrome [OR: 0.63; 95% confidence interval (CI): 0.54, 0.73] and allergic rhinitis (OR: 0.61; 95% CI: 0.54, 0.70), alongside improved physical fitness (standing long jump, standardized mean differences: 0.20-0.27). Early BF initiation (<1 h after birth) reduced neonatal mortality risk by 56% (OR: 0.44; 95% CI: 0.33, 0.61). Regarding long-term offspring outcomes, 2 meta-analyses (2/13, 15.4%) were considered to offer highly suggestive and suggestive evidence, respectively, suggesting the inverse associations of ever BF on overweight/obesity and type 2 diabetes mellitus in adulthood. After GRADE credibility assessment, only 4 of 192 meta-analyses were classified as moderate-quality evidence. CONCLUSIONS: Our findings support the benefits of BF for mothers and their offspring, underscoring the importance of promoting BF practices to improve maternal and child health outcomes. This trial was registered at PROSPERO as CRD42023447328 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023447328).