Workshop on Demographic Analysis and Evaluation

1. Workshop on Demographic Analysis and Evaluation

2. Maternal Mortality Estimation from the Census

3. Maternal Mortality In this lesson, we consider the following questions: Why are we interested in maternal mortality? What is a maternal death? What are the key measures of maternal mortality? Where do maternal mortality estimates come from? How can we calculate maternal mortality ratio from the census?

4. Why We are Interested in Maternal Mortality • Increasing international attention: • 1990 World Summit for Children • 1994 International Conference on Population and Development • 1995 World Conference for Women • 2000 – United Nations identified maternal mortality as the 5th of 8 Millennium Development Goals (MDGs)

5. Introduction • The fifth MDG calls for the improvement of maternal health and, specifically, for the reduction of maternal mortality ratios (maternal deaths per 100,000 live births (MMR)) by three quarters between 1990 and 2015 (UNDP 2010?). • We will use maternal mortality analysis for Namibia as an example of how to estimate and evaluate maternal mortality. • Estimates of maternal mortality for Namibia have varied from • 225 for the period preceding the 1992 NDHS, to • 271 for the period leading up to the 2000 NDHS, to • 449 maternal deaths per 100,000 live births for the decade preceding the latest NDHS.

6. From the 2006/07 NDHS The maternal mortality rate can be converted to a maternal mortality ratio and expressed per 100,000 live births by dividing the rate by the general fertility rate. This general fertility rate that prevailed during this period was 0.117. Using this procedure, the maternal mortality ratio during the 10-year period before the survey is estimated at 449 maternal deaths per 100,000 live births. This figure should be viewed with caution because the number of female deaths that occurred during pregnancy, at delivery, or within two months of delivery is small (86). As a result, the maternal mortality estimates are subject to large sampling errors; the 95 percent confidence intervals indicate that the maternal mortality ratio varies from 341 to 557.

7. From the 2006/07 NDHS Maternal mortality ratios have been estimated for comparable 10-year periods preceding the 1992 and 2000 NDHS surveys. The maternal mortality ratio appears to have increased substantially since the mid-1980s. Over the past seven years it increased from 271 maternal deaths per 100,000 live births for the period 1991-2000 to 449 for the period 1998-2007. The methodology used and the sample sizes implemented in these three surveys do not allow for precise estimates of maternal mortality. While the sampling errors around each of the estimates are large, the confidence intervals around the estimates from the 2000 NDHS and 2006-07 NDHS do not overlap. Thus, it is possible to say with reasonable confidence that maternal mortality in Namibia increased in the recent past. -- 2006/2007 NDHS, p.113

8. Using the Census to Measure Maternal Mortality The 2011 census offers an opportunity to measure maternal mortality without the small numbers of observed deaths and sampling error associated with surveys. The census asked questions about adult mortality and maternal mortality (questionnaire section G). The 2011 census attempts to use a measurement system offering more observations and, in principle, a more accurate result than the NDHS series.

9. What is a Maternal Death? In the International Classification of Diseases and Related Health Problems, Tenth Revision, 1992 (ICD- 10), WHO defines maternal death as: The death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management but not from accidental or incidental causes.

10. Using the Census to Measure Maternal Mortality The census attempts to measure maternal mortality by modifying a time-defined measure of maternal death corresponding to what ICD-10 refers to as a “pregnancy-related death” (PRD), defined as any death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of cause. A PRD, then, may include deaths during pregnancy, at time of childbirth, or following childbirth from unrelated causes. A PRD is easier to measure than a maternal death since it does not require determination of cause of death.

11. Using the Census to Measure Maternal Mortality

12. Introduction • G4 and G5 identify the deceased as female (G4) and age 12-54 (G5) • Adjustment for not-stated age cases follows standard procedure (cf. Wilmoth et al. 2010:4, Hill et al. 2001 chapter 4.1) • G6 allows for removal of all non-illness causes; that is, removal of accident, injury, suicide, violence, witchcraft, and other.

13. Using the Census to Measure Maternal Mortality • G6 and G7 define the death as pregnancy-related. If G6 (What was the cause of his or her death) OR G7 (Did the death occur while pregnant, during childbirth, or within 2 months after childbirth) is yes, then this is a PRD but, having eliminated accidents etc., this is also a maternal death.

14. Measures of Maternal Mortality Maternal mortality ratio (MRR) - Number of maternal deaths during a given time period per 100,000 live births during the same time period Maternal mortality rate - Number of maternal deaths in a given period per 100,000 women of reproductive age during the same time period Adult lifetime risk of maternal death - The probability of dying from a maternal cause during a woman’s reproductive lifespan

15. Calculating MMR • Hill et al. (2001 chapter 4) provide a step-by-step guide to maternal mortality estimation involving data quality evaluation and adjustment in four steps: • 1. Adjustment of population age structure • 2. Evaluation of the completeness of death reporting and adjustment of reported deaths • Evaluation of the completeness of birth reporting and adjustment of reported births • Evaluation of the classification of adult female deaths as maternal

16. Step 1 Adjustment of the age distribution, involves working with the raw age distribution, adjusting each age group proportionately for cases where age is not reported (Hill et al. 2001 section 4.1). We can use PAS spreadsheet ADJAGE.xls.

17. Step 2 The second step, evaluation and adjustment of deaths recorded in a census, may involve a similar adjustment for missing-age deaths, but the primary objective of this step involves evaluation of completeness of death recording using either the Brass Growth Balance Equation or the General Growth Balance technique (United Nations 1983, Hill 1987, Hill et al. 2001) We can use PAS spreadsheet GRBAL.xls.

18. Step 3 The third step, evaluating the completeness of birth recording and adjustment of number of births in order to calculate an adjusted GFR, is described in Hill et al. 2001 section 4.3. A corrected GFR is required for the conversion of MMR into MMRate. We can use PFRatio.xls, ARFE-2.xls, or ARFE-3.xls to implement the adjustment of reported ASFRs, reported births

19. Step 4 The fourth step described by Hill et al. 2001 involves evaluation of the classification of adult female deaths as pregnancy-related. Hill et al. suggest plotting the distribution of proportion of deaths due to maternal causes and the MMR by age.

20. Step 4 Once adjustments to raw data have been made, wherever they can be made, MMR is calculated as the ratio of adjusted maternal deaths to adjusted live births.

21. Finally Lifetime risk (LTR), the hypothetical lifetime risk of maternal deaths to a cohort of women passing through their reproductive ages at the levels of MMR and fertility prevailing, is the final calculation. LTR takes into account the chances of maternal death each time a woman becomes pregnant. MMRate = MMR*GFR and LTR = MMRate*35

22. MMR calculation.xls

23. References Hill, Kenneth. 1987. “Estimating Census and Death Registration Completeness,” Asian and Pacific Population Forum, 1(3):8-13, 23-24. _____, Stanton, Cynthia, Gupta, Neeru. 2001. Measuring Maternal Mortality from a Census: Guidelines for Potential Users. MEASURE Evaluation Manual Series, No. 4.. Carolina Population Center, University of North Carolina at Chapel Hill.

24. References MMEIG et al. 2010. Trends in maternal mortality: 1990 to 2008. Estimates developed by WHO, UNICEF, UNFPA and The World Bank. Geneva: WHO. By the Maternal Mortality Estimation Inter-Agency Group (MMEIG), together with Professor John Wilmoth, Nobuko Mizoguchi, Sarah Zureick, and Reid Hamel. .http://www.childinfo.org/files/Trends_in_Maternal_Mortality_1990_to_2008.pdf Namibia. 2004. Namibia 2004 Millennium Development Goals. Windhoek: Office of the President, National Planning Commission. United Nations Development Programme (UNDP). [2010?] Millennium Development Goals. “What are the Millennium Development Goals?” http://www.undp.org/mdg/basics.shtml. Downloaded November 17, 2011.

25. References Wilmoth, John, Sarah Zureick, Nobuko Mizoguchi, Mie Inoue, and MikkelOestergaard. 2010. “Levels and Trends of Matenral Mortality in the World: The development of new estimates by the United Nations.” http://www.who.int/reproductivehealth/publications/monitoring/MMR_technical_report.pdf World Health Organization (WHO). 1992. International Statistical Classification of Diseases and Related Health Problems, tenth revision, 2nd ed. Geneva: WHO.