Estimates of maternal mortality by the sisterhood method in rural northern Tanzania: a household sample and an antenatal clinic sample

OBJECTIVE: To estimate maternal mortality in two samples of a population in northern Tanzania. SETTING: Rural communities and antenatal clinics, Mbulu and Hanang districts, Arusha region, Tanzania. POPULATION: From a household survey 2,043 men and women aged 15-60, and from an antenatal clinic survey 4,172 women aged 15-59. METHOD: The indirect sisterhood method. MAIN OUTCOME MEASURES: The risk of maternal deaths per 100,000 live births (maternal mortality ratio), and the lifetime risk of a maternal death. RESULTS: The risk of a maternal death per 100,000 live births was 362 (95% CI 269-456) and 444 (95% CI 371-517) for the household and antenatal clinic surveys, respectively. The lifetime risk of maternal death was 1 in 38 and 1 in 31, respectively, for the two surveys. A significantly lower risk of maternal death was observed for the respondents attending antenatal clinics closer to the hospital than for those attending clinics further away: 325 (95% CI 237-413) compared with 561 (95% CI 446-677) per 100,000 live births. Lifetime risk of maternal death was 1 in 42 and 1 in 25, respectively. CONCLUSIONS: The risk of maternal death per 100,000 live births in this area were comparatively high, but in our survey substantially lower than in previous surveys in Tanzania. Increasing distance from the antenatal clinics to the hospital was associated with higher maternal mortality. There was no significant difference between results based on household and antenatal clinic data, suggesting that accessible health facility data using the sisterhood method may provide a basis for local assessment of maternal mortality in developing countries.