Neonatal Mortality Disparities by Gestational Age in European Countries
Authors: Sartorius Victor , Philibert Marianne , Klungsoyr Kari , Klimont Jeannette , Szamotulska Katarzyna , Drausnik Zeljka , Velebil Petr , Mortensen Laust , Gissler Mika , Fresson Jeanne , Nijhuis Jan , Zhang Wei-Hong , Källén Karin , Rihs Tonia A. , Tica Vlad , Matthews Ruth , Smith Lucy , Zeitlin Jennifer ,   Euro-Peristat Network, Farr Alex , Alexander Sophie , Racapé Judith , Vandervelpen Gisèle , Coutellas Vasos , Kyprianou Theopisti , Jirova Jitka , Sakkeus Luule , Abuladze Liili , Blondel Béatrice , Vilain Annick , Durox Mélanie , Heller Guenther , Sziller István , Gunnarsdóttir Johanna , Sól Ólafsdóttir Helga , Sikora Izabela , O'Hara Sinead , Kearns Karen , Cuttini Marina , Loghi Marzia , Boldrini Rosaria , Pappagal Marilena , Marchetti Stefano , Donati Serena , Misins Janis , Zile-Velika Irisa , Isakova Jelena , Lecomte Aline , Pastore Jessica , Álvarez Daniel , Gatt Miriam , Achterberg PW , Broeders Lisa , Akerkar Rupali , Engjom Hilde , Mierzejewska Ewa , Barros Henrique , Puscasiu Lucian , Budianu Mihaela-Alexandra , Cucu Alexandra , Tica Vlad , Lučovnik Miha , Verdenik Ivan , Fernandez Elorriaga Maria , Zurriaga Oscar , Recio Alcaide Adela , Nyman Anastasia , Macfarlane Alison , Scott Sonya , Monteath Kirsten , Morgan Siobhan , Thomas Craig , Magill Sinead , Ceely Greg 
Published: August 2024

Importance

There are wide disparities in neonatal mortality rates (NMRs, deaths &amp;lt;28 days of life after live birth per 1000 live births) between countries in Europe, indicating potential for improvement. Comparing country-specific patterns of births and deaths with countries with low mortality rates can facilitate the development of effective intervention strategies.

Objective

To investigate how these disparities are associated with the distribution of gestational age (GA) and GA-specific mortality rates.

Design, Setting, and Participants

This was a cross-sectional study of all live births in 14 participating European countries using routine data compiled by the Euro-Peristat Network. Live births with a GA of 22 weeks or higher from 2015 to 2020 were included. Data were analyzed from May to October 2023.

Exposures

GA at birth.

Main Outcomes and Measures

The study investigated excess neonatal mortality, defined as a rate difference relative to the pooled rate in the 3 countries with the lowest NMRs (Norway, Sweden, and Finland; hereafter termed the top 3). The Kitagawa method was used to divide this excess into the proportion explained by the GA distribution of births and by GA-specific mortality rates. A sensitivity analysis was conducted among births 24 weeks’ GA or greater.

Results

There were 35 094 neonatal deaths among 15 123 428 live births for an overall NMR of 2.32 per 1000. The pooled NMR in the top 3 was 1.44 per 1000 (1937 of 1 342 528). Excess neonatal mortality compared with the top 3 ranged from 0.17 per 1000 in the Czech Republic to 1.82 per 1000 in Romania. Excess deaths were predominantly concentrated among births less than 28 weeks’ GA (57.6% overall). Full-term births represented 22.7% of the excess deaths in Belgium, 17.8% in France, 40.6% in Romania and 17.3% in the United Kingdom. Heterogeneous patterns were observed when partitioning excess mortality into the proportion associated with the GA distribution vs GA-specific mortality. For example, these proportions were 9.2% and 90.8% in France, 58.4% and 41.6% in the United Kingdom, and 92.9% and 7.1% in Austria, respectively. These associations remained stable after removing births under 24 weeks’ GA in most, but not all, countries.

Conclusions and Relevance

This cohort study of 14 European countries found wide NMR disparities with varying patterns by GA. This knowledge is important for developing effective strategies to reduce neonatal mortality.