Supplementary Material for: Pulmonary Hypertension Association with mortality in Newborns with Giant Omphalocele: A Systematic Review and Meta-Analysis

Introduction: Pulmonary hypertension (PH) is associated with adverse outcomes in infants with omphalocele, but existing studies are limited by small sample sizes and single-center designs. This meta-analysis evaluated the association between PH and mortality, as well as secondary clinical outcomes. Methods: A systematic search in MEDLINE, EMBASE, and Cochrane CENTRAL identified studies of patients with giant omphalocele stratified by PH status. Eligible studies included nonrandomized cohorts, cross-sectional studies, or case controls assessing mortality in this setting. Exclusions were overlapping populations or incomplete data. Primary outcome was mortality. Secondary outcomes included duration of mechanical ventilation (MV), length of hospital and Neonatal Intensive Care Unit (NICU) stay, parenteral nutrition, tracheostomy, high-frequency ventilation, and home oxygen. Risk of bias was assessed using the Newcastle-Ottawa Scale (NOS). The study protocol was registered in PROSPERO (CRD420251025073), and there was no funding for this study. Results: Of 238 studies screened, five retrospective cohorts met criteria, totaling of 258 patients (112 43% with PH and 146 57% without). PH was associated with increased mortality (OR 6.78, 95% CI 2.72–16.88, p < 0.001, I² = 0%) and prolonged MV (mean difference 21.25 days, 95% CI 13.19–29.31, p < 0.001, I² = 0%). Limitations included publication bias, incomplete reporting of clinical variables and the lack of standardized criteria. Conclusion: PH in neonates with omphalocele is associated with higher mortality and prolonged MV. Future studies should clarify risk factors and develop targeted management strategies to improve survival and long-term outcomes.