Objective: To calculate maternal mortality ratio (MMR) for 2006-2018 in the Netherlands and compare with 1993-2005. Describe women’s and obstetric characteristics, causes of death and improvable factors. Design: Prospective cohort study. Setting: Nationwide. Population: 2,304,271 livebirths. Methods: Analysis of all maternal deaths between January 1st, 2006, and December, 31st, 2018 as reported to and audited by the national Audit Committee Maternal Mortality and Morbidity. Main outcome measures: MMR, causes of death, improvable factors. Results: Overall MMR was 6.2 per 100,000 livebirths, a decrease from 12.1 in 1993-2005 (Odds Ratio (OR) 0.5, 95%CI 0.4-0.6). Women with non-Western ethnic background had a slightly increased MMR compared to Dutch women (MMR 6.5 vs 5.0, OR 1.3, 95%CI 0.9-1.9), and was particularly increased among women with a background from Surinam/Dutch Antilles (MMR 14.7 OR 2.9, 95%CI 1.6 – 5.3). Half of all women had an uncomplicated medical history (79/161, 49.1%). Of 172 pregnancy-related deaths within one year postpartum, 103 (60%) had a direct and 69 (40%) an indirect cause. Leading causes within 42 days postpartum were cardiac disease (n=21, 14.8%), hypertensive disorders (n=20, 14.1%) and thrombosis (n=19, 13.4%). For deaths up to one year postpartum, suicide was the third commonest cause (n=20, 11.6%). Improvable factors in care were identified in 76 (47.5%) of all deaths. Conclusions: Maternal mortality halved in 2006-2018 compared to 1993-2005. Unlike before, cardiac disease outnumbered hypertensive disorders as main cause of death. Women with a background from Surinam/Dutch Antilles had a threefold higher risk of death compared to Dutch women.