Temporal Analysis of the Maternal Mortality Scenario in Brazil over the Last 30 Years (1996–2025)

Background/Objectives: Maternal mortality remains a critical indicator of health system performance and social inequality, with the reduction of the Maternal Mortality Ratio (MMR) established as an international priority under the Sustainable Development Goals. In Brazil, despite three decades of health system reforms, the reduction in maternal mortality has occurred unevenly across sociodemographic groups. This study aimed to analyze temporal trends in maternal deaths in Brazil from 1996 to 2025, examining variation by race/color, educational attainment, marital status, type and timing of death, and underlying ICD-10 chapter. Methods: This was an observational, descriptive, and analytical ecological time-series study, conducted according to STROBE recommendations. Secondary, publicly available, aggregated data on maternal deaths (ICD-10 codes O00–O99) among women aged 10–49 years were obtained from the Brazilian Mortality Information System (SIM/DATASUS) covering all Brazilian states from 1996 to 2025. Descriptive analyses of absolute and relative frequencies were performed for each sociodemographic and clinical variable across the study period. Results: Underreporting of race/color declined markedly, from 97% "unknown" in 1996 to residual levels in recent years, revealing a growing predominance of Brown women and persistent overrepresentation of Black women. Single marital status and stable unions increased over time, while married status declined. A marked, transient reversal occurred in 2020–2021, when indirect maternal deaths surpassed direct causes (64% vs. 34%), coinciding with the COVID-19 pandemic, before reverting to the historical pattern by 2022. Chapter XV of the ICD-10 accounted for nearly all deaths throughout the series. Conclusions: Improvements in data completeness did not eliminate persistent racial, educational, and social disparities in Brazilian maternal mortality, reinforcing the need for equity-focused obstetric policies alongside continued strengthening of surveillance systems.