1. Pregnancy-related mortality surveillance: United States;Chang;MMWR Surveill Summ,2003
2. Pregnancy-related mortality in the United States, 1987-1990;Berg;Obstet Gynecol,1996
3. The confidential enquiry into maternal and child health (CEMACH): saving mothers' lives: reviewing maternal deaths to make motherhood safer 2003-2005: the seventh report on confidential enquiry into maternal deaths in the United Kingdom,2007
4. Global burden of maternal death and disability;Abou Zahr;Br Med Bull,2003
5. Maternal mortality in 2000: estimates developed by WHO, UNICEF and UNFPA,2004