Risk factors for pulmonary hemorrhage of very low birth weight infants: a meta-analysis

Pulmonary hemorrhage (PH) is influenced by various perinatal factors. This study aims to identify the risk factors associated with pulmonary hemorrhage in very low birth weight infants and provide a reference for the prevention of this condition in this vulnerable population. A comprehensive literature search was conducted across several databases, including PubMed, Web of Science, Embase, Cochrane Library, Scopus, CNKI, CBM, Wanfang Database and VIP Database, covering publications up to May 20, 2024. The meta-analysis was performed using RevMan 5.4 and Stata 16.0 software to analyze the risk factors for pulmonary hemorrhage in very low birth weight infants. A total of 14 studies were analyzed, comprising 13 case-control studies and 1 cohort study. The combined sample included 17,122 neonates, with 1,363 neonates in the case group and 15,759 neonates in the control group. The meta-analysis identified several risk factors for pulmonary hemorrhage in very low birth weight infants, including patent ductus arteriosus (OR = 2.95, 95% CI: 2.06–4.24), low 5-minute Apgar score (OR = 1.36, 95% CI: 1.01–1.84), use of surfactant (OR = 2.29, 95% CI: 1.40–3.75), respiratory distress syndrome (OR = 6.71, 95% CI: 3.67–12.28), and early-onset sepsis (OR = 6.02, 95% CI: 2.82–12.82). Protective factors identified included complete course of antenatal corticosteroids (OR = 0.36, 95% CI:0.17–0.79). Several risk factors, including patent ductus arteriosus, low 5-minute Apgar scores, use of surfactant, respiratory distress syndrome, and early-onset sepsis, are associated with an increased risk of pulmonary hemorrhage in very low birth weight infants. In contrast, complete course of antenatal corticosteroids has a protective effect in reducing the risk of this severe complication.