Intraventricular haemorrhage (IVH) and associated clinical characteristics in outborn preterm infants <32 weeks undergoing neonatal transport in Western Australia: a retrospective cohort study (2011-2021).
In outborn preterm infants <32 weeks' gestation, IVH risk was more strongly associated with perinatal factors than transport characteristics, with intra-amniotic inflammation, epinephrine use during resuscitation, and inotrope use during transport associated with increased odds of IVH.
Key Findings
Results
IVH occurred in approximately one in five outborn preterm infants under 32 weeks' gestation transported by NETS WA, with severe IVH occurring in nearly one in ten.
IVH occurred in 57/286 (19.9%) on day 1 and 53/275 (19.9%) on day 7 of life.
Severe IVH occurred in 25/286 (8.7%) on day 1 and 27/275 (9.9%) on day 7.
The study included preterm infants <32 weeks' gestation transported by the Newborn Emergency Transport Service of Western Australia (NETS WA) between 2011 and 2021.
Exclusions included congenital anomalies, transfer after day 1 of life, or death before day 1 cranial ultrasound.
Results
Intra-amniotic inflammation was independently associated with increased odds of IVH on day 1 of life.
In multivariable analyses, intra-amniotic inflammation was associated with increased odds of IVH on day 1 (OR 2.47, 95% CI 1.10 to 5.44).
Infants with IVH had greater exposure to intra-amniotic inflammation compared to those without IVH.
This association was identified through logistic regression controlling for other perinatal factors.
Results
Epinephrine use during resuscitation was associated with markedly higher odds of IVH on day 1.
Epinephrine use during resuscitation was associated with higher odds of IVH on day 1 (OR 4.88, 95% CI 1.49 to 17.5).
This finding was identified in multivariable logistic regression analyses.
Epinephrine use likely reflects more severe cardiorespiratory compromise at birth, which may itself contribute to IVH risk.
Results
Inotrope use during transport was associated with substantially increased odds of IVH on both day 1 and day 7.
Inotrope use during transport was associated with IVH on day 1 (OR 7.85, 95% CI 1.35 to 54.6) and day 7 (OR 9.11, 95% CI 1.32 to 72.9).
This was the strongest transport-related factor associated with IVH in multivariable analyses.
Inotrope use during transport reflects hemodynamic instability, which may predispose to cerebrovascular injury.
Results
Continuous positive airway pressure (CPAP) use during transport was associated with lower odds of IVH on day 1.
CPAP during transport was associated with lower odds of IVH on day 1 (OR 0.32, 95% CI 0.10 to 0.88).
This suggests that respiratory support modality during transport may influence IVH risk.
This association was identified in multivariable logistic regression.
Results
Transport mode, duration, and timing intervals were not independently associated with IVH.
Transport mode (e.g., road vs. air), duration of transport, and timing intervals were not associated with IVH in analyses.
This finding suggests that logistical aspects of transport itself are less important than the clinical condition of the infant during transport.
The study spanned 2011 to 2021 and included outborn infants transported to a tertiary perinatal centre.
Results
Infants with IVH had lower gestational age and birth weight and less antenatal steroid exposure compared to those without IVH.
Infants with IVH had lower gestational age and birth weight than those without IVH in bivariate analyses.
Infants with IVH had less antenatal steroid exposure, a key protective intervention for preterm brain injury.
These differences were identified using bivariate tests comparing infants with and without IVH.
What This Means
This research examined brain bleeds (intraventricular haemorrhage, or IVH) in premature babies born before 32 weeks of pregnancy who were born outside of a major hospital and needed emergency transport to a specialist centre in Western Australia between 2011 and 2021. The study found that about one in five of these babies (nearly 20%) had a brain bleed detected in the first week of life, and about one in ten had a severe bleed. The strongest risk factors were related to the baby's condition around the time of birth — including signs of infection in the womb (intra-amniotic inflammation), needing adrenaline during resuscitation at birth, and needing medications to support blood pressure during transport. Babies who received CPAP (a form of breathing support) during transport had lower rates of brain bleeds.
Importantly, factors related to the transport itself — such as how long the journey took, what time of day it occurred, or whether the baby traveled by road or air — were not associated with whether a baby developed a brain bleed. This suggests that it is the baby's underlying medical condition and the quality of immediate care around the time of birth and during transport that matter most, not the logistics of the transport journey itself.
This research suggests that efforts to reduce brain bleeds in premature babies born outside specialist centres should focus on improving care during and immediately after birth, such as ensuring more babies receive antenatal steroids before birth and optimizing resuscitation and stabilization. Collaboration across regional and tertiary perinatal networks may help ensure that even babies born in smaller hospitals receive the best possible early care.
Desai S, Joseph M, George K, Tan K, Dempsey Z, Cooper M, et al.. (2026). Intraventricular haemorrhage (IVH) and associated clinical characteristics in outborn preterm infants <32 weeks undergoing neonatal transport in Western Australia: a retrospective cohort study (2011-2021).. BMJ open. https://doi.org/10.1136/bmjopen-2026-120592