[Maternal mortality trend in the state of Rio de Janeiro, Brazil, 2006-2018, according to the ICD-MM classification].

The study aimed to analyze the trend in the maternal mortality ratio (MMR) according to the ICD classification for maternal mortality (ICD-MM) classification in the state of Rio de Janeiro, Brazil, from 2006 to 2018. This was a time trend study of MMR in Rio de Janeiro according to type of death (direct or indirect) and groups of causes in the World Health Organization (WHO) ICD-MM. MMR was calculated with data from Brazilian Mortality Information System (SIM) and Brazilian Information System on Live Births (SINASC). Trends were estimated with the Joinpoint Regression Program. Of the 2,192 maternal deaths in the state, 61% were from direct causes, 34% from indirect causes, and 5% unspecified. There was a downward trend in total MMR and MMR from direct causes: -1.2% (95%CI: -2.3; -0.1) per year and -3.8% (95%CI: -4.9; -2.6) from 2006 to 2015, respectively. For direct causes, according to the ICD-MM, group 2 (hypertensive causes) predominated, but there was a decrease in eclampsia. Next came group 5 (other complications, featuring category O90 and subcategory O90.3 - peripartum cardiomyopathy) and group 1 (pregnancy with abortive outcomes). Indirect causes showed stability, and the majority belonged to category O99 and its subcategories related to cardiovascular and respiratory diseases. MMR in Rio de Janeiro showed a downward trend from 2006 to 2018, although far short of WHO recommendations and with different patterns among the causes. ICD-MM was useful for identifying major groups of causes, but it is necessary to disaggregate by subcategories to adequately elucidate the etiology of maternal death.