1. Global, regional, and national levels of maternal mortality, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015 [published correction appears in Lancet. 2017 Jan 7;389(10064):e1];GBD 2015 Maternal Mortality Collaborators;Lancet,2016
2. World Health Organization. “Trends in maternal mortality 2000 to 2017: estimates by WHO, UNICEF, UNFPA, World Bank Group and the United Nations Population Division.” (2019). Available from: https://apps.who.int/iris/handle/10665/327595 Accessed June 3, 2022.
3. Maternal mortality in the United States: Changes in coding, publication, and data release, 2018;Hoyert;Natl Vital Stat Rep,2020
4. Maternal mortality in the United States: updates on trends, causes, and solutions;Collier;Neoreviews,2019
5. Centre for Maternal and Child Enquiries. Saving mothers' lives: reviewing maternal deaths to make motherhood safer: 2006–8: a review;McClure;Br J Anaesth,2011