Risk factors and population attributable fraction for large-for-gestational-age and macrosomic births in low- and middle-income countries between 2000 and 2025: a protocol for systematic review and meta-analysis.

introductionLarge-for-gestational-age (LGA) and macrosomic births pose significant maternal and neonatal health risks, particularly in low- and middle-income countries (LMICs), where access to care are often limited. Despite well-established associations between LGA, macrosomia, and various risk factors, the relative contributions of these factors remain underexplored in LMICs. This study aims to identify risks factors for LGA and macrosomia in LMICs, with an emphasis on modifiable ones, and quantify their population attributable fractions (PAFs). METHODS AND ANALYSIS: A systematic review will be conducted across the following databases: MEDLINE, Scopus and ProQuest Central and regional databases (Africa Index Medicus, Index Medicus for South Asia and Latin America and Caribbean literature of health sciences). Eligible studies will include observational studies, reviews and interventional research conducted between 2000 and 2025 that report on prevalence or association of risk factors for large-for-gestational-age (LGA) and/or macrosomia births in low- and middle-income countries (LMICs). Data extraction will encompass study characteristics, prevalence/incidence estimates, risk factor distributions and measures of association. Quality assessment will be performed by two independent reviewers using the Newcastle-Ottawa Scale for observational cohort, case-control and cross-sectional studies. While Cochrane Risk of Bias Tool will be used for randomised controlled trials and a Measurement Tool to Assess Quality of Systematic Reviews 2 (AMSTAR-2) for systematic reviews and meta-analyses. Meta-analyses using a random-effects model, which accounts for population heterogeneity, will synthesise risk estimates for factors examined in three or more studies from LMICs, up-to-date meta-analysis including all relevant studies identified through our search. Population attributable fractions for individual and combined risk factors will be calculated. ETHICS AND DISSEMINATION: This systematic review will use only previously published information. Ethical approval is therefore not required. The results will be submitted for publication in a peer-reviewed journal and the findings will be presented at international conferences to engage relevant stakeholders including policymakers and public health organisations in LMICs with the aim of informing the development of targeted interventions to reduce the burden of LGA and macrosomia births in the region.