Living Longer by Achieving MDG 5: Estimating the Impact of Maternal Mortality Reduction on Reproductive Age Life Expectancy in sub-saharan Africa

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1 Living Longer by Achieving MDG 5: Estimating the Impact of Maternal Mortality Reduction on Reproductive Age Life Expectancy in sub-saharan Africa Linnea Zimmerman*, Vladimir Canudas-Romo*, Li Liu, Amy Tsui * Department of Population, Family and Reproductive Health Department of International Health Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA Department of Biostatistics, University of Copenhagen, Copenhagen K, Denmark Introduction The first year in human history when women worldwide enjoyed a longer life expectancy at birth than men arrived in the mid-2000s. 1 However, if confined to reproductive ages, namely 15 to 50, that female life expectancy advantage still lags. To eliminate the remaining disadvantage will require significant reductions in maternal mortality. It is well known that Millennium Development Goal 5 aims at a 75% reduction in the maternal mortality ratio by With new funding commitments being made and a growing global momentum in support of lowering maternal mortality, 2 3 we discuss in this analysis the demographic implications of achieving MDG 5. Currently, a great disparity exists in maternal mortality ratios (MMR) between developed and developing countries, much larger than for any other health statistical measure. 4 5 This reflects, to a large degree, differential quality in health care systems across countries. In 2005, 536 thousand maternal deaths occurred worldwide, with more than 533 thousand occurring in developing countries. 6 For developing regions, the estimated maternal mortality ratio is 402 deaths per 100,000 live births, and the highest regional MMR is found in Sub-Saharan Africa (905 deaths per 100,000 live births). Strikingly high MMRs for the developing world have been seen in Europe and North America at the beginning of the 20 th century. The MMR was as high as 612 in England and Wales in 1848, declining to 282 by 1939 and then to 10 by This pattern of rapid decline in MMRs during the first half of the 20 th century is common for other developed countries, and invites the question of the impact of maternal mortality reduction on improving women s life expectancy? Because maternal deaths occur during women s reproductive period (ages 15 to 49), it is expected that the impact would be 1

2 greatest on lengthening the life expectancy during women s reproductive age. We coined the term female reproductive-aged life expectancy (RALE) for a life expectancy calculated from age 15 to 49. RALE is suited for studying maternal mortality impact because it is conditioned on survival to age 15 and takes into account all competing causes of death. 8 9 Preliminary Results: How Much Can Reducing Maternal Mortality Contribute to Female Survival? Although a relatively rare event, maternal mortality occupies an important role in demographic and epidemiological transitions With cause eliminated life tables and decomposition methods 13 the specific contribution of maternal mortality to the rise in the female survival between age 15 and 50 can be assessed. In the industrialized world and from countries with reasonably reliable vital statistics 14 the estimated increase in RALE from 1930 to 1960 was 29.6 to 34.5 years. Of the 4.9-year increase, half a year was gained when maternal mortality was eliminated, that is 10% of the overall gain. A similar assessment of the levels of maternal mortality, reproductive age life expectancy and RALE in the absence of maternal mortality in Sub-Saharan Africa 15 is presented in Table 1. The RALE values range from 27 to 33 years in these populations. The possible gains by eliminating maternal mortality vary from 0.15 year in Central African Republic to 1.5 years in Chad, or from 4% to 46% contribution of the total potential change in RALE respectively. [Table 1 and Figure 1 about here] While constrained by the quality of the maternal mortality data, 16 we can cautiously predict a large number of the Sub-Saharan African countries will gain 0.5 years in their RALE values if maternal mortality is eliminated. This amount of increase mirrors the historical experience in the developed world and some other newly industrialized countries. 2

3 Conclusion: Meeting MDG 5 This analysis demonstrates the potential contribution of eliminating childbearingassociated risks of death, as opposed to other causes of deaths, between the ages 15 and 50. What was not previously known was that, on average, a five-year gain in RALE for females occurred in the twentieth century in the developed and some developing countries. Of this gain, between ten to thirty percent is due to maternal mortality, a share that is possibly greater in Sub-Saharan African countries today. Reducing maternal mortality by 75%, female life expectancy between ages 15 and 50 could increase, on average, 0.4 year (0.5 year if 100% eliminated). Moreover, the contribution of eliminating maternal mortality could reach as much as one year of life for some African countries. This gain in RALE may seem a small increase to those in policy circles, but the added survival time takes place during the most productive ages of human life and carries with it non-trivial socio-economic implications for family and workforce. The demographic implications of eliminating maternal deaths on female survival in prime adult ages also point to the need to understand both the roles of other causes of death and reporting patterns. The apparent ambitiousness of MDG 5 is based on the historical declines observed over short time frames in the Western world. More recently in some developing countries significant reductions in maternal mortality have also occurred to support the optimistic pace of change Concerns have been raised about the one-size-fits-all strategy to achieve MDG-5 reductions. 19 Approaches and policies to reduce maternal mortality will need to be context specific and address other contributing factors that affect female survival through reproduction, including adequate nutrition in childhood, access to safe water and reduced exposure to HIV infection. Maternal mortality is a relatively rare event, yet it is still a very important component of reproductive-aged life expectancy. In developed countries, maternal mortality statistics underestimate incidence, on average by a third, and the inaccuracies are much greater in 3

4 developing countries Monitoring levels and trends in maternal mortality and causes of death for these critical ages for both women and men should be a top priority among health system strengthening efforts in all countries that are lagging in their achievement of MDG 5. 4

5 References 1. Barford A, Dorling D, Smith GD, Shaw M. Life expectancy: women now on top everywhere. BMJ 2006;332: Horton R. What will it take to stop maternal deaths? Lancet 2009;374(9699): Rosenfield A, Maine D, Freedman L. Meeting MDG-5: an impossible dream? Lancet 2006;368(9542): Donnay F. Maternal survival in developing countries: what has been done, what can be achieved in the next decade. International Journal of Gynecology and Obstetrics 2000;70: Mantel GD, Moodley J. Can a developed country s maternal mortality review be used as the gold standard for a developing country? European Journal of Obstetrics and Gynecology and Reproductive Biology 2002;100: Hill K, Thomas K, AbouZahr C, on behalf of the Maternal Mortality Working Group. Estimates of maternal mortality worldwide between 1990 and 2005: an assessment of available data. Lancet 2007; 370: Loudon I. Death in childbirth: An international study of maternal care and maternal mortality London: Clarendon Press. 8. Wilmoth J. The lifetime risk of maternal mortality: concept and measurement. Bull World Health Organ 2009;87: World Health Organization. Maternal Mortality in 2005: Estimates Developed by WHO, UNICEF, UNFPA and the World Bank Geneva: WHO. 10. University of California, Berkeley, Max Planck Institute for Demographic Research. Human Mortality Database Lee R. The demographic transition: three centuries of fundamental change. The Journal of Economic Perspectives 2003;17: Omran AR. The epidemiologic transition: a theory of the epidemiology of population change. Milbank Mem Fund Q. 1971; 49(4): Beltrán-Sánchez H, Preston SH, Canudas-Romo V. An integrated approach to causeof-death analysis: cause-deleted life tables and decompositions of life expectancy. Demographic Research 2008;19: Preston S. Mortality Patterns in National Populations New York: Academic Press. 15. Macro International Inc. Demographic and Health Surveys Stanton C, Abderrahim N, Hill K. An Assessment of DHS Maternal Mortality Indicators. Studies in Family Planning, 2000; 31(2): Ronsmans C, Graham WJ, on behalf of The Lancet Maternal Survival Series steering group. Maternal mortality: who, when, where, and why. Lancet 2006;368: Koblinsky M. Reducing maternal mortality - learning from bolivia, china, egypt, honduras, indonesia, jamaica, and zimbabwe Washington D.C.: The World Bank. 19. Costello A, Azad K, Barnett S. An alternative strategy to reduce maternal mortality. Lancet 2006;368:

6 20. Rosenfield A, Maine D. Maternal mortality-a neglected tragedy: Where is the M in MCH? Lancet 1985;326:

7 Table 1. Reproductive-aged life expectancy (RALE) in life tables with all causes of death and maternal mortality eliminated (RALE-NoMM), Sub-Saharan countries. 7

8 Figure 1. Relative percentage increase in female reproductive-aged life expectancy when eliminating maternal mortality, selected countries in Sub- Saharan Africa