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Maternal mortality ratio

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Maternal MortalityCauses of Death

What you should know about this indicator

Maternal deaths are defined as a death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and site of pregnancy, from any cause related or aggravated by the pregnancy or its management, but not from accidental or incidental causes.

Data on maternal mortality and other relevant variables are obtained through databases maintained by WHO, UNPD, UNICEF, and the World Bank Group. Data available from countries varies in terms of the source and methods.

Given the variability of the sources of data, different methods are used for each data source in order to arrive at country estimates that are comparable and permit regional and global aggregation.

The current methodology employed by the Maternal Mortality Estimation Inter-Agency Group (MMEIG) in this round followed an improved approach that built directly upon methods used to produce the previous rounds of estimates published by the MMEIG since 2008.

Estimates for this round were generated using a Bayesian approach, referred to as the Bayesian maternal mortality estimation model, or BMat model. This enhanced methodology uses the same core estimation method as in those previous rounds, but adds refinements to optimize the use of country-specific data sources and excludes late maternal deaths. It therefore provides more accurate estimates, and a more realistic assessment of certainty about those estimates.

The new model still incorporates the same covariates which are;

  • the Gross Domestic Product per capita based on purchasing power parity conversion (GDP),
  • the general fertility rate (GFR)
  • proportion of births attended by a skilled health worker (SAB).

The MMEIG has developed a method to adjust existing data in order to take into account these data quality issues and ensure the comparability of different data sources. This method involves assessment of data for underreporting and, where necessary, adjustment for incompleteness and misclassification of deaths as well as development of estimates through statistical modelling for countries with no reliable national level data.

Maternal mortality ratio
The estimated number of women who die from per 100,000 live births, based on data from death certificates, large-scale surveys, and statistical modeling.
Source
UN MMEIG (2023); WHO Mortality Database (2024); UN, World Population Prospects (2024); Gapminder (2010) – with major processing by Our World in Data
Last updated
July 8, 2024
Next expected update
July 2025
Date range
1751–2020
Unit
deaths per 100,000 live births

Related research and writing

A dark blue background with a lighter blue world map superimposed over it. Yellow text that says Global Health by Our World in Data

Global Health

Esteban Ortiz-Ospina and Max Roser
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Maternal Mortality

Max Roser and Hannah Ritchie

Explore charts that include this data

Sources and processing

This data is based on the following sources

The United Nations Maternal Mortality Estimation Inter-Agency Group (MMEIG) – comprising WHO, the United Nations Children’s Fund (UNICEF), the United Nations Population Fund (UNFPA), the World Bank Group and the United Nations Department of Economic and Social Affairs, Population Division (UNDESA/Population Division) has collaborated with external technical experts on a new round of estimates covering 2000 to 2020, in addition to the previous data covering 1985 to 2000. The estimates represent the most up to date, internationally-comparable MMEIG estimates of maternal mortality, using refined input data and methods from previous rounds.

Retrieved on
July 8, 2024
Retrieved from
https://www.who.int/publications/i/item/9789240068759
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
Trends in maternal mortality 2000 to 2020: estimates by WHO, UNICEF, UNFPA, World Bank Group and UNDESA/ Population Division. Geneva: World Health Organization; 2023. Licence: CC BY-NC-SA 3.0 IGO.

The WHO mortality database is a collection death registration data including cause-of-death information from member states.

Where they are collected, death registration data are the best source of information on key health indicators, such as life expectancy, and death registration data with cause-of-death information are the best source of information on mortality by cause, such as maternal mortality and suicide mortality.

WHO requests from all countries annual data by age, sex, and complete ICD code (e.g., 4-digit code if the 10th revision of ICD was used). Countries have reported deaths by cause of death, year, sex, and age for inclusion in the WHO Mortality Database since 1950.

The WHO only includes data, which are properly coded according to the International Classification of Diseases (ICD). Today the database is maintained by the WHO Division of Data, Analytics and Delivery for Impact (DDI) and contains data from over 120 countries and areas. Data reported by member states and selected areas are displayed in this portal’s interactive visualizations if the data are reported to the WHO mortality database in the requested format and at least 65% of deaths were recorded in each country and year.
Retrieved on
July 26, 2024
Retrieved from
https://platform.who.int/mortality
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
WHO Division of Data, Analytics and Delivery for Impact (DDI), World Health Organization (2024)

World Population Prospects 2024 is the 28th edition of the official estimates and projections of the global population that have been published by the United Nations since 1951. The estimates are based on all available sources of data on population size and levels of fertility, mortality and international migration for 237 countries or areas. If you have questions about this dataset, please refer to their FAQ. You can also explore data sources for each country or visit their main page for more details.

Retrieved on
July 11, 2024
Retrieved from
https://population.un.org/wpp/Download/
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
United Nations, Department of Economic and Social Affairs, Population Division (2024). World Population Prospects 2024, Online Edition.

Maternal Mortality is defined as a death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and site of pregnancy, from any cause related or aggravated by the pregnancy or its management, but not from accidental or incidental causes. Maternal mortality ratio (usually abbreviated MMR) is the number of maternal deaths during a given time period per 100,000 live births during the same time period

Retrieved on
July 8, 2024
Retrieved from
https://www.gapminder.org/data/documentation/gd010/
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
Based on free material from GAPMINDER.ORG (https://www.gapminder.org/data/documentation/gd010/), CC-BY LICENSE

How we process data at Our World in Data

All data and visualizations on Our World in Data rely on data sourced from one or several original data providers. Preparing this original data involves several processing steps. Depending on the data, this can include standardizing country names and world region definitions, converting units, calculating derived indicators such as per capita measures, as well as adding or adapting metadata such as the name or the description given to an indicator.

At the link below you can find a detailed description of the structure of our data pipeline, including links to all the code used to prepare data across Our World in Data.

Read about our data pipeline
Notes on our processing step for this indicator
  • The dataset combines three sources: WHO Mortality Database (before 1985), Gapminder (before 1985, if WHO Mortality Database data are unavailable), UN MMEIG (1985 onwards). The WHO Mortality Database and Gapminder contain reported figures from countries, and are likely to underestimate the true maternal mortality figures. The UN MMEIG aims to estimates the true rate, by adjusting for underreporting and misclassification. Sudden jumps in mortality rate in 1985 are a consequence of switching data sources (from reported to estimated figures).
  • For the years between 1950 - 1985 we calculated the maternal mortality ratio and maternal mortality rate based on the number of maternal deaths from the WHO mortality database and live births and female population of reproductive age from the UN WPP.
  • Where the reported maternal deaths in the WHO Mortality Database differed significantly from the estimated figures in the UN MMEIG data, we opted not to include them.
  • Where a data point is attached to a range of years in the Gapminder data set, we used the midpoint of the range.
  • The UN MMEIG data shown (post 1985) is the point estimate - this means there is a 50% chance that the true measure lies above this point, and a 50% chance that the true value lies below this point.
  • We calculated regional aggregates by summing the maternal deaths and live births of all countries in the region and then calculating the MMR based on these figures.

Reuse this work

  • All data produced by third-party providers and made available by Our World in Data are subject to the license terms from the original providers. Our work would not be possible without the data providers we rely on, so we ask you to always cite them appropriately (see below). This is crucial to allow data providers to continue doing their work, enhancing, maintaining and updating valuable data.
  • All data, visualizations, and code produced by Our World in Data are completely open access under the Creative Commons BY license. You have the permission to use, distribute, and reproduce these in any medium, provided the source and authors are credited.

Citations

How to cite this page

To cite this page overall, including any descriptions, FAQs or explanations of the data authored by Our World in Data, please use the following citation:

“Data Page: Maternal mortality ratio”, part of the following publication: Max Roser and Hannah Ritchie (2013) - “Maternal Mortality”. Data adapted from UN MMEIG (WHO, UNICEF, UNFPA, World Bank Group and UNDESA/ Population Division), WHO Mortality Database, United Nations, Gapminder. Retrieved from https://ourworldindata.org/grapher/maternal-mortality [online resource]
How to cite this data

In-line citationIf you have limited space (e.g. in data visualizations), you can use this abbreviated in-line citation:

UN MMEIG (2023) and other sources – with major processing by Our World in Data

Full citation

UN MMEIG (2023); WHO Mortality Database (2024); UN, World Population Prospects (2024); Gapminder (2010) – with major processing by Our World in Data. “Maternal mortality ratio” [dataset]. UN MMEIG (WHO, UNICEF, UNFPA, World Bank Group and UNDESA/ Population Division), “Trends in maternal mortality 2020”; WHO Mortality Database, “WHO Mortality Database”; United Nations, “World Population Prospects”; Gapminder, “Maternal mortality ratio V1” [original data]. Retrieved June 18, 2025 from https://ourworldindata.org/grapher/maternal-mortality