International Variation and Trends of Intraventricular Hemorrhage in Very Preterm Infants

Georgia Hollens; Tim Schindler; Malcolm Battin; Gil Klinger; Mark Adams; Maximo Vento; Antonino Santacroce; Stellan Håkansson; Tetsuya Isayama; Mikael Norman; Satoshi Kusuda; Liisa Lehtonen; Kjell Helenius; Neena Modi; Prakesh S Shah; Kei Lui; iNeo Neonatal Network

doi:10.1159/000546714

International Variation and Trends of Intraventricular Hemorrhage in Very Preterm Infants

Neonatology. 2025;122(5):570-585. doi: 10.1159/000546714. Epub 2025 May 31.

Authors

Georgia Hollens¹, Tim Schindler^{1

2}, Malcolm Battin³, Gil Klinger⁴, Mark Adams⁵, Maximo Vento⁶, Antonino Santacroce⁷, Stellan Håkansson⁸, Tetsuya Isayama⁹, Mikael Norman^{10

11}, Satoshi Kusuda¹², Liisa Lehtonen^{13

14}, Kjell Helenius^{13

14}, Neena Modi¹⁵, Prakesh S Shah^{16

17}, Kei Lui^{1

2}; iNeo Neonatal Network

Affiliations

¹ School of Clinical Medicine, University of New South Wales, Sydney, New South Wales, Australia.
² Royal Hospital for Women, Sydney, New South Wales, Australia.
³ Newborn Services, Auckland City Hospital, Grafton, New Zealand.
⁴ Department of Neonatal Intensive Care, Schneider Children's Medical Center of Israel, Petah Tikva, and Tel Aviv University, Tel Aviv, Israel.
⁵ Department of Neonatology, University and University Hospital Zurich, Zurich, Switzerland.
⁶ Division of Neonatology, Health Research Institute Hospital La Fe, Valencia, Spain.
⁷ Department of Women and Children, University Hospital, Siena, Italy.
⁸ Department of Clinical Sciences/Pediatrics, Umeå University Hospital, Umeå, Sweden.
⁹ Division of Neonatology, National Center for Child Health and Development, Tokyo, Japan.
¹⁰ Department of Neonatal Medicine, Karolinska University Hospital, Stockholm, Sweden.
¹¹ Division of Pediatrics, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
¹² Neonatal Research Network of Japan, Kyorin University, Tokyo, Japan.
¹³ Department of Pediatrics and Adolescent Medicine, Turku University Hospital, Turku, Finland.
¹⁴ Department of Clinical Medicine, University of Turku, Turku, Finland.
¹⁵ Section of Neonatal Medicine, School of Public Health, Imperial College London, London, UK.
¹⁶ Department of Pediatrics, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
¹⁷ Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.

Abstract

<p>Introduction: We aimed to investigate international variation in gestational age (GA) specific severe intraventricular hemorrhage (IVH) rates, among infants of <30 weeks' GA from the neonatal networks of 11 high-income countries/region.

Methods: Retrospective cohort study of outcomes of grade 3/4 IVH rates and composite of g3/4 IVH or death in GA groups of 22-23, 24-25, 26-27, and 28-29 weeks infants admitted to networks of Australia and New Zealand, Canada, Finland, Israel, Italy (Tuscany), Japan, Spain, Sweden, Switzerland, and the UK. Their risk adjusted trends across 3 epochs (2007-11, 2012-15, and 2016-19) were also evaluated.

Results: Outcomes of 165,329 infants (median GA 27 weeks, birthweight 950 g) were analyzed. Overall, the lowest grade 3/4 IVH rate was observed in Japan (6.4%) and the highest in Israel (16.1%). The overall gestation-specific rate of IVH grade 3/4 were 25.8%, 18.6%, 9.0%, and 3.8% and composite outcome of grade 3/4 IVH/death rates 52.2%, 33.6%, 15.6%, and 6.7% for the 22-23, 24-25, 26-27, and 28-29 weeks' GA groups, respectively. These inter-network variations were greater at lower GA. In epoch comparisons, almost all networks showed significant decreases in GA specific composite outcome rates, particularly in the 26-27 week' GA group. Japan and Canada demonstrated significant decreases in each GA group while Spain demonstrated significant decreases in each GA group except for 22-23 weeks' gestation.

Conclusions: Rates of grade 3/4 IVH and composite outcome rates varied internationally and have decreased over time. Identification of the driving factors behind variations may allow for opportunities for practice review and improvement. </p>.

Keywords: Intraventricular hemorrhage; Neonatal networks; Variations; Very preterm infants.

Publication types

Multicenter Study

MeSH terms

Cerebral Hemorrhage* / epidemiology
Cerebral Hemorrhage* / mortality
Cerebral Intraventricular Hemorrhage* / epidemiology
Cerebral Intraventricular Hemorrhage* / mortality
Female
Gestational Age
Humans
Infant, Extremely Premature*
Infant, Newborn
Infant, Premature, Diseases* / epidemiology
Male
Retrospective Studies