Research exposes global inequities in maternal health risks across a woman’s life

New findings published in The Lancet Global Health expose substantial global and regional disparities in the cumulative burden of life-threatening maternal morbidity across the female reproductive life span.

The study, co-authored by researchers at the Leverhulme Centre for Demographic Science and London School of Hygiene & Tropical Medicine, is the first to calculate the lifetime risk of maternal near miss for 40 countries spanning Asia, Africa, the Middle East, and Latin America from 2010 onwards.

A “maternal near miss” is defined as a woman who survived, but almost died from a life-threatening complication of pregnancy and childbirth. The World Health Organization (WHO) identifies cases of maternal near misses using clinical, laboratory, and lifesaving intervention-based criteria of organ dysfunction such as blood transfusion or emergency hysterectomy.

This novel study provides a cross-country comparison of the likelihood that a female individual aged 15 years will experience a maternal near miss before the age of 50, given the prevalence of maternal near miss morbidity, fertility, and mortality levels in each country for a specific year.

The lifetime risk of maternal near miss is one in 20 or higher in nine countries, seven of which are in sub-Saharan Africa. The highest risk is one in six in Guatemala (2016) which is almost 45 times higher than the lowest risk of one in 269 in Vietnam (2010).

Countries with a high burden of maternal near miss morbidity are likely to also have a high burden of maternal mortality across the female reproductive life course. Global variation in the lifetime risk of maternal death is even greater than for maternal near miss, with a 750-fold difference in risk from one in 17 in Nigeria (2012) to one in 12,778 in Japan (2010).

These disparities are driven by differences in the level of obstetric risk, fertility levels, and survival in reproductive ages. For example, most countries with a high lifetime risk of maternal near miss have a high total fertility rate, such as the Democratic Republic of Congo, and vice versa for countries like China.

Lead author Ursula Gazeley, Postdoctoral Researcher at the Leverhulme Centre for Demographic Science and Demographic Science Unit said, “Our results expose substantial global and regional inequalities in the cumulative burden of maternal near miss morbidity across the reproductive life course. The lifetime risk of maternal near miss emphasizes the magnitude of these disparities and the need for the global community to improve maternal outcomes.”

Surviving a complication of this severity can impact women’s physical, psychological, sexual, social, and economic well-being in the long-term. However, as women may experience more than one pregnancy over their lifetimes, existing estimates of maternal near miss prevalence fail to account for the cumulative risk from repeat pregnancy.

Co-author Antonino Polizzi, DPhil student at the Leverhulme Centre for Demographic Science said, “Maternal near miss events reflect the ability of a health care system to save a woman’s life when life-threatening complications arise, and are testament to the importance of expanding access to, and the quality of, emergency obstetric care.”

The study also found substantial cross-country inequality in the lifetime risk of severe maternal outcome—the risk that a female individual aged 15 years will either die from a maternal cause or experience near miss morbidity during her lifetime. The risk ranges from one in 201 in Malaysia (2014) to one in five in Guatemala (2016) and exceeds one in 20 in 11 countries, eight of which are in sub-Saharan Africa.

Dr. José Manuel Aburto, Marie Skłodowska-Curie Fellow at the Leverhulme Centre for Demographic Science and Associate Professor at London School of Hygiene & Tropical Medicine concludes, “The lifetime risk of severe maternal outcome emphasizes the true burden to women’s lives, their families, communities, health systems, and the work still needed to end preventable forms of maternal morbidity and mortality. Let this be an important tool for advocacy and an urgent call on the global community to redouble its efforts.”

The study recommends applying disease classification codes to WHO criteria to enhance measurement in routine health records, encourage wider adoption, and improve consistency in measuring maternal near miss across different income settings. Encouraging compliance to WHO’s criteria will therefore ensure that maternal near miss data from Europe and North America can be effectively incorporated into future estimates of lifetime risk.

A key limitation of the study is the restriction of eligible maternal near miss prevalence data that identified cases using the standard WHO criteria or versions modified for low-resource settings. Since few high-income countries use these criteria, this results in an incomplete picture of global inequalities in the lifetime risk of maternal near miss. Additionally, the study included subnational estimates of maternal near miss data, which may not be representative of national-level trends.

The study concludes that the development of surveillance systems to institutionalize routine monitoring of maternal near miss complications is essential to improving the availability of national-level data.