Racial/Ethnic Disparities in Pregnancy-Related Deaths - United States, 2007-2016.

Approximately 700 women die in the United States each year as a result of pregnancy or its complications, and significant racial/ethnic disparities in pregnancy-related mortality exist (1). Data from CDC's Pregnancy Mortality Surveillance System (PMSS) for 2007-2016 were analyzed. Pregnancy-related mortality ratios (PRMRs) (i.e., pregnancy-related deaths per 100,000 live births) were analyzed by demographic characteristics and state PRMR tertiles (i.e., states with lowest, middle, and highest PRMR); cause-specific proportionate mortality by race/ethnicity also was calculated. Over the period analyzed, the U.S. overall PRMR was 16.7 pregnancy-related deaths per 100,000 births. Non-Hispanic black (black) and non-Hispanic American Indian/Alaska Native (AI/AN) women experienced higher PRMRs (40.8 and 29.7, respectively) than did all other racial/ethnic groups. This disparity persisted over time and across age groups. The PRMR for black and AI/AN women aged ≥30 years was approximately four to five times that for their white counterparts. PRMRs for black and AI/AN women with at least some college education were higher than those for all other racial/ethnic groups with less than a high school diploma. Among state PRMR tertiles, the PRMRs for black and AI/AN women were 2.8-3.3 and 1.7-3.3 times as high, respectively, as those for non-Hispanic white (white) women. Significant differences in cause-specific proportionate mortality were observed among racial/ethnic populations. Strategies to address racial/ethnic disparities in pregnancy-related deaths, including improving women's health and access to quality care in the preconception, pregnancy, and postpartum periods, can be implemented through coordination at the community, health facility, patient, provider, and system levels.

Vital Signs: Pregnancy-Related Deaths, United States, 2011-2015, and Strategies for Prevention, 13 States, 2013-2017.

BACKGROUND: Approximately 700 women die from pregnancy-related complications in the United States every year. METHODS: Data from CDC's national Pregnancy Mortality Surveillance System (PMSS) for 2011-2015 were analyzed. Pregnancy-related mortality ratios (pregnancy-related deaths per 100,000 live births; PRMRs) were calculated overall and by sociodemographic characteristics. The distribution of pregnancy-related deaths by timing relative to the end of pregnancy and leading causes of death were calculated. Detailed data on pregnancy-related deaths during 2013-2017 from 13 state maternal mortality review committees (MMRCs) were analyzed for preventability, factors that contributed to pregnancy-related deaths, and MMRC-identified prevention strategies to address contributing factors. RESULTS: For 2011-2015, the national PRMR was 17.2 per 100,000 live births. Non-Hispanic black (black) women and American Indian/Alaska Native women had the highest PRMRs (42.8 and 32.5, respectively), 3.3 and 2.5 times as high, respectively, as the PRMR for non-Hispanic white (white) women (13.0). Timing of death was known for 87.7% (2,990) of pregnancy-related deaths. Among these deaths, 31.3% occurred during pregnancy, 16.9% on the day of delivery, 18.6% 1-6 days postpartum, 21.4% 7-42 days postpartum, and 11.7% 43-365 days postpartum. Leading causes of death included cardiovascular conditions, infection, and hemorrhage, and varied by timing. Approximately sixty percent of pregnancy-related deaths from state MMRCs were determined to be preventable and did not differ significantly by race/ethnicity or timing of death. MMRC data indicated that multiple factors contributed to pregnancy-related deaths. Contributing factors and prevention strategies can be categorized at the community, health facility, patient, provider, and system levels and include improving access to, and coordination and delivery of, quality care. CONCLUSIONS: Pregnancy-related deaths occurred during pregnancy, around the time of delivery, and up to 1 year postpartum; leading causes varied by timing of death. Approximately three in five pregnancy-related deaths were preventable. IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Strategies to address contributing factors to pregnancy-related deaths can be enacted at the community, health facility, patient, provider, and system levels.

Pregnancy-Related Mortality in the United States, 2011-2013.

OBJECTIVE: To update national population-level pregnancy-related mortality estimates and examine characteristics and causes of pregnancy-related deaths in the United States during 2011-2013. METHODS: We conducted an observational study using population-based data from the Pregnancy Mortality Surveillance System to calculate pregnancy-related mortality ratios by year, age group, and race-ethnicity groups. We explored 10 cause-of-death categories by pregnancy outcome during 2011-2013 and compared their distribution with those in our earlier reports since 1987. RESULTS: The 2011-2013 pregnancy-related mortality ratio was 17.0 deaths per 100,000 live births. Pregnancy-related mortality ratios increased with maternal age, and racial-ethnic disparities persisted with non-Hispanic black women having a 3.4 times higher mortality ratio than non-Hispanic white women. Among causes of pregnancy-related deaths, the following groups contributed more than 10%: cardiovascular conditions ranked first (15.5%) followed by other medical conditions often reflecting pre-existing illnesses (14.5%), infection (12.7%), hemorrhage (11.4%), and cardiomyopathy (11.0%). Relative to the most recent report of Pregnancy Mortality Surveillance System data for 2006-2010, the distribution of cause-of-death categories did not change considerably. However, compared with serial reports before 2006-2010, the contribution of hemorrhage, hypertensive disorders of pregnancy, and anesthesia complications declined, whereas that of cardiovascular and other medical conditions increased (population-level percentage comparison). CONCLUSION: The pregnancy-related mortality ratio and the distribution of the main causes of pregnancy-related mortality have been relatively stable in recent years.

Pregnancy-related mortality in the United States, 2006-2010.

OBJECTIVE: To update national population-level pregnancy-related mortality estimates and examine characteristics and causes of pregnancy-related deaths in the United States during 2006-2010. METHODS: We used data from the Pregnancy Mortality Surveillance System and calculated pregnancy-related mortality ratios by year and age group for four race-ethnicity groups: non-Hispanic white, non-Hispanic black, Hispanic, and other. We examined causes of pregnancy-related deaths by pregnancy outcome during 2006-2010 and compared causes of pregnancy-related deaths since 1987. RESULTS: The 2006-2010 pregnancy-related mortality ratio was 16.0 deaths per 100,000 live births (20,959,533 total live births). Specific race-ethnicity pregnancy-related mortality ratios were 12.0, 38.9, 11.7, and 14.2 deaths per 100,000 live births for non-Hispanic white, non-Hispanic black, Hispanic, and other race women, respectively. Pregnancy-related mortality ratios increased with maternal age for all women and within all age groups, non-Hispanic black women had the highest risk of dying from pregnancy complications. Over time, the contribution to pregnancy-related deaths of hemorrhage, hypertensive disorders of pregnancy, embolism, and anesthesia complications continued to decline, whereas the contribution of cardiovascular conditions and infection increased. Seven of 10 categories of causes of death each contributed from 9.4% to 14.6% of all 2006-2010 pregnancy-related deaths; cardiovascular conditions ranked first. CONCLUSION: Relative to previous years, during 2006-2010, the U.S. pregnancy-related mortality ratio increased as did the contribution of cardiovascular conditions and infection to pregnancy-related mortality. Although the identification of pregnancy-related deaths may be improving in the United States, the increasing contribution of chronic diseases to pregnancy-related mortality suggests a change in risk profile of the birthing population. LEVEL OF EVIDENCE: II.

Race, ethnicity, and nativity differentials in pregnancy-related mortality in the United States: 1993-2006.

OBJECTIVE: To compare trends in and causes of pregnancy-related mortality by race, ethnicity, and nativity from 1993 to 2006. METHODS: We used data from the Pregnancy Mortality Surveillance System. For each race, ethnicity, and nativity group, we calculated pregnancy-related mortality ratios and assessed causes of pregnancy-related death and the time between the end of pregnancy and death. RESULTS: Race, ethnicity, and nativity-related minority women contributed 40.7% of all U.S. live births but 61.8% of the 7,487 pregnancy-related deaths during 1993-2006. Pregnancy-related mortality ratios were 9.1 and 7.5 deaths per 100,000 live births among U.S.- and foreign-born white women, respectively, and slightly higher at 9.6 and 11.6 deaths per 100,000 live births for U.S.- and foreign-born Hispanic women, respectively. Relative to U.S.-born white women, age-standardized pregnancy-related mortality ratios were 5.2 and 3.6 times higher among U.S.- and foreign-born black women, respectively. However, causes and timing of death within 42 days postpartum were similar for U.S.-born white and black women with cardiovascular disease, cardiomyopathy, and other pre-existing medical conditions emerging as chief contributors to mortality. Hypertensive disorders, hemorrhage, and embolism were the most important causes of pregnancy-related death for all other groups of women. CONCLUSION: Except for foreign-born white women, all other race, ethnicity, and nativity groups were at higher risk of dying from pregnancy-related causes than U.S.-born white women after adjusting for age differences. Integration of quality-of-care aspects into hospital- and state-based maternal death reviews may help identify race, ethnicity, and nativity-specific factors for pregnancy-related mortality. LEVEL OF EVIDENCE: III.

Pregnancy-related mortality surveillance--United States, 1991--1999.

PROBLEM/CONDITION: The risk of death from complications of pregnancy has decreased approximately 99% during the twentieth century, from approximately 850 maternal deaths per 100,000 live births in 1900 to 7.5 in 1982. However, since 1982, no further decrease has occurred in maternal mortality in the United States. In addition, racial disparity in pregnancy-related mortality ratios persists; since 1940, mortality ratios among blacks have been at least three to four times higher than those for whites. The Healthy People 2000 objective for maternal mortality of no more than 3.3 maternal deaths per 100,000 live births was not achieved during the twentieth century; substantial improvements are needed to meet the same objective for Healthy People 2010. REPORTING PERIOD COVERED: This report summarizes surveillance data for pregnancy-related deaths in the United States for 1991-1999. DESCRIPTION OF SYSTEM: The Pregnancy Mortality Surveillance System was initiated in 1987 by CDC in collaboration with state health departments and the American College of Obstetricians and Gynecologists Maternal Mortality Study Group. Health departments in the 50 states, the District of Columbia, and New York City provide CDC with copies of death certificates and available linked outcome records (i.e., birth certificates or fetal death certificates) of all deaths occurring during or within 1 year of pregnancy. State maternal mortality review committees, the media, and individual providers report a limited number of deaths not otherwise identified. Death certificates and relevant birth or fetal death certificates are reviewed by clinically experienced epidemiologists at CDC to determine whether they are pregnancy-related. RESULTS: During 1991-1999, a total of 4,200 deaths were determined to be pregnancy-related. The overall pregnancy-related mortality ratio was 11.8 deaths per 100,000 live births and ranged from 10.3 in 1991 to 13.2 in 1999. The pregnancy-related mortality ratio for black women was consistently higher than that for white women for every characteristic examined. Older women, particularly women aged >/= 35 years and women who received no prenatal care, were at increased risk for pregnancy-related death. The distribution of the causes of death differed by pregnancy outcome. Among women who died after a live birth (i.e., 60% of the deaths), the leading causes of death were embolism and pregnancy-induced hypertension. INTERPRETATION: The reported pregnancy-related mortality ratio has substantially increased during 1991-1999, probably because of improved ascertainment of pregnancy-related deaths. Black women continued to have a 3-4 times higher pregnancy-related mortality ratio than white women. In addition, pregnancy-related mortality has the largest racial disparity among the maternal and child health indicators. Reasons for this difference could not be determined from the available data. PUBLIC HEALTH ACTIONS: Continued surveillance and additional studies should be conducted to monitor the magnitude of pregnancy-related mortality, to identify factors that contribute to the continuing racial disparity in pregnancy-related mortality, and to develop effective strategies to prevent pregnancy-related mortality for all women. In addition, CDC is working with state health departments, researchers, health-care providers, and other stakeholders to improve the ascertainment and classification of pregnancy-related deaths.