WHO systematic review of maternal mortality and morbidity: methodological issues and challenges

We followed the standard methodology for systematic reviews. We prepared a protocol and a form for data extraction that identify key characteristics on study and reporting quality. An extensive search was conducted for the years 1997–2002 including electronic and hand searching.We screened the titles and abstracts of about 65,000 citations identified through 11 electronic databases as well as various other sources. Four thousand six hundred and twenty-six full-text reports were critically appraised and 2443 are included in the review so far. Approximately one third of the studies were conducted in Asia and Africa. The reporting quality was generally low with definitions for conditions and the diagnostic methods often not reported.There are unique challenges and issues regarding the search, critical appraisal and summarizing epidemiological data in this systematic review of prevalence/incidence studies. More methodological studies and discussion to advance the field will be useful. Considerable efforts including leadership, consensus building and resources are required to improve the standards of monitoring burden of disease.Levels of maternal mortality and morbidity tell us about the risk attributable to pregnancy and childbirth as well as the performance of health systems in terms of access to health care and the quality of care provided. However, accurate assessment of these indicators has been problematic. The World Health Organization (WHO) has developed estimates of maternal mortality [1,2], anaemia during pregnancy, low birth weight and unsafe abortion at national, regional and global levels using modelling techniques. The lack of good quality data for many countries and different methodologies used to estimate levels of mortality complicate monitoring of the trends and comparisons between countries [3,4].Although considerable amounts of facility-based data on maternal morbidity are generated, these may not reflect the actual health status of women in the whol