Intended for healthcare professionals

CCBYNC Open access
Research

Maternal mortality in eight European countries with enhanced surveillance systems: descriptive population based study

BMJ 2022; 379 doi: https://doi.org/10.1136/bmj-2022-070621 (Published 16 November 2022) Cite this as: BMJ 2022;379:e070621

Linked Editorial

Accurate surveillance of maternal deaths is an international priority

  1. Caroline Diguisto, obstetrician, epidemiologist1 2 3,
  2. Monica Saucedo, epidemiologist2,
  3. Athanasios Kallianidis, medical doctor4,
  4. Kitty Bloemenkamp, professor in obstetrics, maternal health5,
  5. Birgit Bødker, senior consultant in obstetrics6,
  6. Marta Buoncristiano, public health researcher7,
  7. Serena Donati, public health researcher7,
  8. Mika Gissler, professor in epidemiology8 9 10,
  9. Marianne Johansen, senior consultant in obstetrics11,
  10. Marian Knight, professor of maternal and child population health1,
  11. Miroslav Korbel, associated professor gynaecology and obstetrics12,
  12. Alexandra Kristufkova, associated professor of gynaecology and obstetrics12,
  13. Lill T Nyflot, senior consultant in obstetrics and maternal health researcher13 14,
  14. Catherine Deneux-Tharaux, research director in perinatal epidemiology2
  1. 1National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, UK
  2. 2Université Paris Cité, CRESS UMR 1153, Obstetrical Perinatal and Pediatric Epidemiology Research Team, EPOPé, INSERM, INRAE, Paris, France
  3. 3Pôle de gynécologie obstétrique, médecine fœtale, médecine et biologie de la reproduction, centre Olympe de Gouges, CHRU de Tours, 37 044 Tours, France; Université de Tours, 37032 Tours, France
  4. 4Department of Obstetrics and Gynaecology, Leiden University Medical Center, Leiden, Netherlands
  5. 5Department of Obstetrics, Division Women and Baby, Birth Centre Wilhelmina's Children Hospital, University Medical Centre Utrecht, Utrecht University, Utrecht, Netherlands
  6. 6Nordsjællands Hospital, Hillerød, Denmark
  7. 7National Centre for Disease Prevention and Health Promotion, Istituto Superiore di Sanità - Italian National Institute of Health, Rome, Italy
  8. 8Department of Knowledge Brokers, THL Finnish Institute for Health and Welfare, Helsinki, Finland
  9. 9Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden
  10. 10Region Stockholm, Academic Primary Health Care Centre, Stockholm, Sweden
  11. 11Department of Obstetrics, Rigshospitalet University Hospital, Copenhagen, Denmark
  12. 121st Department of Obstetrics and Gynaecology, Faculty of Medicine, Comenius University in Bratislava, Slovak Republic
  13. 13Norwegian Research Centre for Women's Health, Oslo University Hospital, Oslo, Norway
  14. 14Department of Obstetrics, Drammen Hospital, Drammen, Norway
  1. Correspondence to: C Deneux-Tharaux catherine.deneux-tharaux{at}inserm.fr (or @Epope_Inserm on Twitter)
  • Accepted 28 September 2022

Abstract

Objective To compare maternal mortality in eight countries with enhanced surveillance systems.

Design Descriptive multicountry population based study.

Setting Eight countries with permanent surveillance systems using enhanced methods to identify, document, and review maternal deaths. The most recent available aggregated maternal mortality data were collected for three year periods for France, Italy, and the UK and for five year periods for Denmark, Finland, the Netherlands, Norway, and Slovakia.

Population 297 835 live births in Denmark (2013-17), 301 169 in Finland (2008-12), 2 435 583 in France (2013-15), 1 281 986 in Italy (2013-15), 856 572 in the Netherlands (2014-18), 292 315 in Norway (2014-18), 283 930 in Slovakia (2014-18), and 2 261 090 in the UK (2016-18).

Outcome measures Maternal mortality ratios from enhanced systems were calculated and compared with those obtained from each country’s office of vital statistics. Age specific maternal mortality ratios; maternal mortality ratios according to women’s origin, citizenship, or ethnicity; and cause specific maternal mortality ratios were also calculated.

Results Methods for identifying and classifying maternal deaths up to 42 days were very similar across countries (except for the Netherlands). Maternal mortality ratios up to 42 days after end of pregnancy varied by a multiplicative factor of four from 2.7 and 3.4 per 100 000 live births in Norway and Denmark to 9.6 in the UK and 10.9 in Slovakia. Vital statistics offices underestimated maternal mortality by 36% or more everywhere but Denmark. Age specific maternal mortality ratios were higher for the youngest and oldest mothers (pooled relative risk 2.17 (95% confidence interval 1.38 to 3.34) for women aged <20 years, 2.10 (1.54 to 2.86) for those aged 35-39, and 3.95 (3.01 to 5.19) for those aged ≥40, compared with women aged 20-29 years). Except in Norway, maternal mortality ratios were ≥50% higher in women born abroad or of minoritised ethnicity, defined variously in different countries. Cardiovascular diseases and suicides were leading causes of maternal deaths in each country. Some other conditions were also major contributors to maternal mortality in only one or two countries: venous thromboembolism in the UK and the Netherlands, hypertensive disorders in the Netherlands, amniotic fluid embolism in France, haemorrhage in Italy, and stroke in Slovakia. Only two countries, France and the UK, had enhanced methods for studying late maternal deaths, those occurring between 43 and 365 days after the end of pregnancy.

Conclusions Variations in maternal mortality ratios exist between high income European countries with enhanced surveillance systems. In-depth analyses of differences in the quality of care and health system performance at national levels are needed to reduce maternal mortality further by learning from best practices and each other. Cardiovascular diseases and mental health in women during and after pregnancy must be prioritised in all countries.

Footnotes

  • Contributors: CD, MS, AKallianidis, and CDT designed the study. CDT and MS were responsible for the French data. AKallianidis and KB were responsible for the data from the Netherlands. MB and SD were responsible for the Italian data. BB and MJ were responsible for the Danish data. MG was responsible for the Finnish data. LN was responsible for the Norwegian data. MKnight was responsible for the UK data. MKorbel and AKristufkova were responsible for the Slovak data. CD collected the data. CD, MS, AKallianidis, and CDT did the analysis and wrote the draft manuscript. All authors contributed significantly to writing the final version of the manuscript. The corresponding author attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted. CDT is the guarantor.

  • Funding: This study received no specific funding.

  • Competing interests: All authors have completed the ICMJE uniform disclosure form at https://www.icmje.org/disclosure-of-interest/ and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.

  • The lead author (the manuscript’s guarantor) affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as originally planned (and, if relevant, registered) have been explained.

  • Dissemination to participants and related patient and public communities: Dissemination of the results to women, families, healthcare practitioners, and policy makers will be undertaken at the international level through the INOSS website and social media account. The results will be presented at the FIGO conference in Paris (2023). At the national level, the people in charge of the obstetric surveillance systems of each country involved in the study will disseminate the results to healthcare practitioners through professional bodies’ websites and conferences and to women through patients’ associations.

  • Provenance and peer review: Not commissioned; externally peer reviewed.

Data availability statement

No additional data available.

http://creativecommons.org/licenses/by-nc/4.0/

This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

View Full Text