Pregnancy-related mortality in the United States, 1991–1997

OBJECTIVE: To describe trends in pregnancy-related mortality and risk factors for pregnancy-related deaths in the United States for the years 1991 through 1997. METHODS: In collaboration with the American College of Obstetricians and Gynecologists and state health departments, the Pregnancy Mortality Surveillance System, part of the Division of Reproductive Health at the Centers for Disease Control and Prevention, has collected information on all reported pregnancy-related deaths occurring since 1979. Data include those present on death certificates and, when available, matching birth or fetal death certificates. Data are reviewed and coded by clinically experienced epidemiologists. The pregnancy-related mortality ratio was defined as pregnancy-related deaths per 100,000 live births. RESULTS: The reported pregnancy-related mortality ratio increased from 10.3 in 1991 to 12.9 in 1997. An increased risk of pregnancy-related death was found for black women, older women, and women with no prenatal care. The leading causes of death were embolism, hemorrhage, and other medical conditions, although the percent of all pregnancy-related deaths caused by hemorrhage declined from 28% in the early 1980s to 18% in the current study period. CONCLUSION: The reported pregnancy-related mortality ratio has increased, probably because of improved identification of pregnancy-related deaths. Black women continue to have an almost four-fold increased risk of pregnancy-related death, the greatest disparity among the maternal and child health indicators. Although review of pregnancy-related deaths by states remains an important public health function, such work must be expanded to identify factors that influence the survival of women with serious pregnancy complications.