Background: Pulmonary hemorrhage (PH) is a catastrophic event associated with significant morbidity and mortality among preterm infants. Understanding PH risk factors in preterm newborns, particularly those in low-to-middle-income countries like Vietnam, remains limited. This study aimed to investigate the risk factors and short-term outcomes of PH in very preterm infants. Methods: We conducted an observational study of newborns aged < 72 hours with gestational age < 32 weeks, admitted to our unit from April 1, 2018 to March 31, 2019. Results: Of 118 recruited newborns, 28 (23.7%) had PH. The logistic regression analysis showed that intubation within 24 first hours, blood transfusion, and coagulation disorders within the first 3 days were risk factors for PH (aOR = 4.594, 95% CI = 1.200-17.593; aOR = 5.394, 95% CI = 1.243-23.395 and aOR = 7.242 95% CI = 1.838-28.542, respectively). Intra-ventricular hemorrhage (IVH) and mortality rates were higher in patients with PH compared to those without (p<0.001). The length of invasive ventilation was longer in the PH group (p<0.001). Conclusion: We have identified intubation, blood transfusion, and coagulation disorders shortly after birth as risk factors for PH in very preterm infants, which was associated with increased mortality and occurrence of IVH.

The authors have declared no competing interest.

The authors received no financial support for the research, authorship, and publication of this article.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study protocol was reviewed and approved by the Institutional Review Board of Children's Hospital 1 (IORG0007285, FWA00009748, Approval number: 2784/QĐ-BVNĐ1, On October 16th, 2019).

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Data for this study are contained within patient medical records and are not publicly available due to privacy restrictions. The data are available from the corresponding author, Thu-Tinh Nguyen, upon reasonable request.