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. 2025 Feb;114(2):319-331.
doi: 10.1111/apa.17429. Epub 2024 Sep 23.

Centralisation of extremely preterm births and decreased early postnatal mortality in Sweden, 2004-2007 versus 2014-2016

Christian Gadsbøll  1   2 , Lars J Björklund  1   2 , Mikael Norman  3   4 , Thomas Abrahamsson  5   6 , Magnus Domellöf  7 , Anders Elfvin  8   9 , Aijaz Farooqi  7 , Lena Hellström-Westas  10 , Stellan Håkansson  7 , Karin Källén  11 , Erik Normann  10 , Fredrik Serenius  10 , Karin Sävman  8   9 , Petra Um-Bergström  12   13 , Ulrika Ådén  4   5   6   14 , David Ley  1   2
Affiliations

Centralisation of extremely preterm births and decreased early postnatal mortality in Sweden, 2004-2007 versus 2014-2016

Christian Gadsbøll et al. Acta Paediatr. 2025 Feb.

Abstract

Aim: We evaluated the increased centralisation of extremely preterm (EPT) births in Sweden in relation to the changes in mortality and morbidity.

Methods: Population-based data covering Swedish live births from 22 + 0 to 26 + 6 weeks of gestation during 2004-2007 and 2014-2016 were analysed for associations between time-period, birth within (inborn) or outside (outborn) regional centres, and outcomes.

Results: Among 1626 liveborn infants, 703 were born in 2004-2007 and 923 in 2014-2016. Birth outside (vs. within) regional centres was associated with a higher infant mortality even after adjustment for birth cohort, gestational age, birthweight standard deviation score and infant sex (adjusted odds ratio 2.01, 95% confidence interval 1.31-3.07, p = 0.001). The higher 1-year mortality in outborn infants was mainly due to more deaths within 24 h after birth. Outborn infants had a higher incidence of intraventricular haemorrhage grade 3-4 than inborn infants (22% vs. 14% in 2004-2007, and 22% vs. 13% in 2014-2016, both p < 0.05). While survival to 1 year without major morbidity increased in inborn infants (33%-40%, p = 0.008), it remained unchanged in outborn infants (29% vs. 30%, p = 0.88).

Conclusion: Centralisation of EPT births contributed to a lower 1-year mortality in 2014-2016 than that in 2004-2007, attributed to a decrease in deaths before 24 h among inborn infants.

Keywords: centralisation of births; extremely preterm; infant mortality; intraventricular haemorrhage; outborn.

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Conflict of interest statement

The authors have no conflicts of interest to declare.

Figures

FIGURE 1
FIGURE 1
Distribution (n) of infants born in (inborn) or outside (outborn) regional centres in 2004–2007 and 2014–2016 according to gestational age.
FIGURE 2
FIGURE 2
Survival to 1 year in infants born within (inborn) or outside (outborn) regional centres with level III–IV neonatal intensive care facilities in 2004–2007 and 2014–2016. Survival at 1 year of age noted as percent (%) of infants born alive. Tests of equality of survival distribution (LogRank) for the four groups showed p < 0.001.
See this image and copyright information in PMC

References

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