Improving Maternal Mortality: Comprehensive Reporting for All Pregnancy Outcomes

Objective: To demonstrate the impact of inadequate standardization and population coverage on the ability to measure and improve maternal mortality in the United States. Data Sources: The CDC Wonder system for the years 2000-2015 using the following definitions of maternal mortality and associated ICD-CM-10 codes: 1) Maternal deaths up to 42 days after delivery (A34, O00-O99, except O96-O97); 2) Maternal deaths within one year after delivery (A34, O00-O99, except O97); 3) All maternal deaths (A34, O00-O99). Study Design: For each year between 2000-2015, we provided maternal deaths, live births, and calculated maternal mortality ratios (MDR). For deaths within 42 days, we also calculated adjusted mortality ratios (ADR). Principal Findings: Maternal mortality comparisons which utilize inconsistent definitions and apply non-validated statistical adjustments produce specious results. Conclusions: Variation and inconsistency in definitions, coding, and other reporting anomalies render the current aggregated vital statistics on maternal mortality inadequate for accurate trending and service impact studies. The definition of maternal mortality must be expanded to all outcomes of pregnancy: births, induced abortions, and natural fetal losses.