Maternal mortality from the sample is based on mothers' deaths in the first 42 days after giving birth, divided by the number of births in the sampled group, based on population reconstitutions from linked civil certificates in LINKS, Zeeland. The national annual number of births nationwide and in Zeeland are from Statistics of Population Change in the Netherlands ("Statistiek van den loop der bevolking van Nederland"). Maternal mortality statistics are from 5-year reports on causes of death for regions and the nation "Vijfjarig overzicht van de sterfte naar den leeftijd en de oorzaken van den dood in elke gemeente van Nederland" for the years 1880 (1875–1879), 1885 (1880–1884), 1890 (1885–1889), 1895 (1890–1894), 1900 (1895–1899) (van den Boomen, 2021). Annual maternal deaths nationally 1875–1900 are taken from the "Statistics of Mortality by the causes of death over the year 1903" (Statistieken van den sterfte naar den oorzaken van den dood over het jaar 1903). Annual deaths after 1900 nationally and Zeeland from theS Statistics of Mortality by the causes of ddeath over the year...(Statistieken van den sterfte naar den oorzaken van den dood over het jaar…) 1901–1913.”