Decomposing estimates of the maternal mortality ratio

The goal of this paper is to better appreciate how estimates of the maternal mortality ratio (MMR) are related to estimates of fertility and female reproductive age mortality and how changes in the MMR can be placed within the broader context of recent changes in fertility and adult mortality. To achieve this goal an alternative expression for the maternal mortality ratio, that incorporates measures of fertility and mortality, will be presented. This expression will also be used as a tool for comparing estimates of MMRs produced by the United Nations interagency working group with estimates from different data sources to better understand why there are large discrepancies in estimates for individual countries. Special consideration is given to the set of countries that have experienced large changes in female reproductive age mortality due to the rise in AIDS mortality.