Interventions to Support Breastfeeding: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force.

Importance: Interventions to support breastfeeding may help individuals and families initiate breastfeeding or breastfeed exclusively or for a prolonged period of time. Objective: To systematically review the evidence on the benefits and harms of breastfeeding interventions to support the US Preventive Services Task Force in updating its 2016 recommendation. Data Sources: Studies included in the previous review were reevaluated for inclusion and updated searches in MEDLINE, CINAHL, Cochrane Central Register of Controlled Trials, and PsycINFO through June 3, 2024. Surveillance for new evidence in targeted publications through January 24, 2025. Study Selection: Randomized clinical trials that evaluated a primary care-relevant intervention designed to support breastfeeding. Of 290 full-text articles reviewed, 90 met inclusion criteria. Data Extraction and Synthesis: Independent critical appraisal of all provisionally included studies. Data were independently abstracted by one reviewer and confirmed by another. Main Outcomes and Measures: Child and maternal health outcomes, prevalence, and duration of any and exclusive breastfeeding, and harms related to interventions. Results: Ninety trials (N = 49 597) reported in 125 publications were included. The evidence represented individuals from diverse backgrounds and interventions that varied in timing, delivery, and duration. There was limited and mixed evidence on the effectiveness of breastfeeding support interventions on infant health outcomes (10 trials [n = 6592]) and maternal symptoms of anxiety, depression, and well-being (9 trials [n = 2334]). Pooled analyses indicated beneficial associations between breastfeeding support interventions and any or exclusive breastfeeding for up to and at 6 months (any breastfeeding: risk ratio, 1.13 [95% CI, 1.05-1.22]; 37 trials [n = 13 579] and exclusive breastfeeding: risk ratio, 1.46 [95% CI, 1.20-1.78]; 37 trials [n = 14 398]). There was no relationship between interventions and breastfeeding initiation or breastfeeding at 12 months. Conclusions and Relevance: The updated evidence confirms that breastfeeding support interventions can increase the prevalence of any or exclusive breastfeeding up to and at 6 months. Future efforts should focus on how to best provide this support consistently for all individuals making feeding decisions for their infants.