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Changes in mortality rates among extremely preterm infants born before 25 weeks' gestation: Comparison between the

Kazuo Itabashi1, Tokuo Miyazawa1, Satoshi Kusuda2

  • 1Department of Pediatrics, Showa University School of Medicine, Tokyo, Japan.

Early Human Development
|February 6, 2021
PubMed

Insights

Mortality rates for extremely preterm infants born before 25 weeks gestation in Japan significantly improved between 2005 and 2010. However, care for infants born at 22 weeks gestation remains challenging.

Area of Science:

  • Neonatalogy
  • Perinatal Medicine
  • Public Health

Background:

  • There is ongoing debate regarding improvements in outcomes for extremely preterm infants (<25 weeks gestation).
  • Assessing trends in mortality for this vulnerable population is crucial for evaluating healthcare advancements.

Purpose of the Study:

  • To investigate changes in hospitalization mortality rates among extremely preterm infants in Japan.
  • To analyze trends in mortality stratified by gestational age between 2005 and 2010.

Main Methods:

  • Retrospective analysis of nationwide survey data from Japan.
  • Comparison of mortality rates for infants born <25 weeks gestation in 2005 versus 2010.
  • Statistical adjustment for explanatory variables to determine the probability of death.

Main Results:

  • Overall mortality for infants born <25 weeks gestation decreased from 36.4% in 2005 to 25.6% in 2010.
  • Gestational age-specific mortality rates generally decreased, with notable improvements at 22 and 23 weeks gestation.
  • Adjusted odds ratio for death in 2010 was significantly lower (0.597), particularly for infants born at 23 weeks gestation (aOR 0.439).

Conclusions:

  • Mortality rates for extremely preterm infants (<25 weeks gestation) in Japan have shown steady improvement from 2005 to 2010.
  • Despite overall improvements, the management and outcomes for infants born at 22 weeks gestation continue to present significant challenges.
Abstract

Keywords:
Extremely preterm infantsMortalityNationwide surveyNeonatal intensive care unit

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