Maternal mortality in Sweden 1988–2007: more deaths than officially reported

OBJECTIVE: To obtain more accurate calculations of maternal and pregnancy-related mortality ratios in Sweden from 1988 to 2007 by using information from national registers and death certificates. DESIGN: A national register-based study, supplemented by a review of death certificates. SETTING: Sweden, 1988-2007. POPULATION: The deaths of 27 957 women of reproductive age (15-49 years). METHODS: The Swedish Cause of Death Register, Medical Birth Register, and National Patient Register were linked. All women with a diagnosis related to pregnancy in at least one of these registers within 1 year prior to death were identified. Death certificates were reviewed to ascertain maternal deaths. Maternal mortality ratio (the number of maternal deaths/100 000 live births, excluding and including suicides), and pregnancy-related mortality ratio (number of deaths within 42 days after termination of pregnancy, irrespective of cause of death/100 000 live births) were calculated. MAIN OUTCOME MEASURES: Direct and indirect maternal deaths and pregnancy-related deaths. RESULTS: The maternal mortality ratio in Sweden, based on the current method of identifying maternal deaths, was 3.6. After linking registers and reviewing death certificates, we identified 64% more maternal deaths, resulting in a ratio of 6.0 (or 6.5 if suicides are included). The pregnancy-related mortality ratio was 7.3. A total of 478 women died within a year after being recorded with a diagnosis related to pregnancy. CONCLUSIONS: By including the 123 cases of maternal death identified in this study, the mean maternal mortality ratio from 1988 to 2007 was 64% higher than reported to the World Health Organization.