Alarming Rise in Maternal Mortality Rates in the US: Implications for Healthcare

Importance  

Evidence suggests that maternal mortality has been increasing in the U.S. Complete estimates do not exist. Long-term trends in maternal mortality rates (MMR) were estimated for all states by racial and ethnic groups.

Aim  

To quantify trends in MMR (maternal deaths per 100,000 live births) by state for 5 mutually exclusive racial and ethnic groups using a Bayesian extension of the generalized linear model network.

Design, environment and participants  

Observational study using vital registration and census data from 1999 to 2019 in the US. Pregnant or newly pregnant individuals ages 10 to 54 were included.

Main results and measures  

Maternal mortality rates (MMR)

Results 

In 2019, maternal mortality rates (MMR) in most states were higher among American Indian, Alaska Native, and Black populations than among Asian, Native Hawaiian, or other Pacific Islander populations; Hispanic; and white populations.

Between 1999 and 2019, state median observed MMRs increased from 14.0 (IQR, 5.7-23.9) to 49.2 (IQR, 14.4-88.0) among the American Indian and Native American population. Alaska, 26.7 (IQR, 18.3-32.9) to 55.4 (IQR, 31.6-74.5) among blacks, 9.6 (IQR, 5.7-12.6) to 20.9 (IQR, 12.1-32.8) among Asian, Native Hawaiian, or other Pacific Islander populations, 9.6 (IQR, 6.9-11.6) to 19.1 (IQR, 11.6-24.9) among the Hispanic population, and from 9.4 (IQR, 7.4-11.4) to 26.3 (IQR, 20.3-33.3) among the white population.

In each year between 1999 and 2019, Black people had the highest median state MMR. The American Indian and Alaska Native population had the largest increases in state median MMRs between 1999 and 2019.

Since 1999, state median MMRs have increased for all racial and ethnic groups in the U.S. and for American Indians and Alaska Natives; Asian, Native Hawaiian, or other Pacific Islander; and Black populations each saw their highest median state MMRs in 2019.

Conclusion and relevance 

While maternal mortality remains unacceptably high among all racial and ethnic groups in the US, American Indian, Alaska Native, and Black people are at increased risk, particularly in several states where these inequalities have not previously been highlighted .

Median state MMRs for American Indian/Alaska Native and Asian/Native Hawaiian/Other Pacific Islander populations continue to increase, even after the adoption of a pregnancy check box on death certificates.

The average state MMR for the black population remains the highest in the U.S. Comprehensive mortality surveillance for all states through vital registration identifies states and racial and ethnic groups with the greatest potential to improve mortality. maternal mortality.

Comments

High maternal mortality rates found in the northern and Midwestern mountain states in addition to the South, a region traditionally known for having high rates

The study is the first analysis of its kind for each state, showing differences in each state by racial and ethnic groups.

A new study by researchers at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington and Mass General Brigham found that maternal mortality rates have worsened from 1999 to 2019, affecting some racial and ethnic groups and states. more than others. Their results are published in the Journal of the American Medical Association (JAMA).

" Maternal mortality is a crisis in the United States . These rates have increased in recent decades and were exacerbated by the pandemic," said co-author Allison Bryant, MD, MPH, senior medical director of health equity at Mass General. Brigham. "Our study sheds light on wide disparities within maternal mortality rates: the spectrum of maternal death differentially affects some ethnic and racial populations."

Maternal mortality, or maternal death, is a death during or up to one year after the end of pregnancy. According to the Centers for Disease Control and Prevention, common causes of maternal death include mental health conditions, including death by suicide and overdoses related to substance use disorder, excessive bleeding (hemorrhage), heart and coronary conditions , infection, thromboembolism (blood clot), cardiomyopathy (a disease of the heart muscle) and hypertensive disorders of pregnancy (related to high blood pressure). Previous research has found that rates of different causes of maternal mortality vary by race and ethnicity.

Bryant and co-authors used data from the National Vital Statistics System on deaths and live births in each state and racial/ethnic group between 1999 and 2019. They then used a modeling process to create estimates of maternal deaths during those periods. This model estimated maternal mortality for each state and each race and ethnicity per 100,000 live births without potentially violating any person’s privacy.

"These disparities in maternal mortality are just the tip of the iceberg and tell us a lot about the health risks faced by people in states where these deaths are most likely to occur," said Greg Roth, associate professor in the Division of Cardiology and Director of the IHME Cardiovascular Health Metrics Program. "In the U.S., maternal deaths are often caused by vascular diseases such as severe high blood pressure or blood clots. Therefore, maternal deaths share many of the same factors as heart attacks, strokes, and stroke. heart failure. Our state-by-state research emphasizes where we need to focus our prevention efforts and which groups are suffering the most."

For all racial and ethnic groups, maternal mortality more than doubled during this time period. These rates have been increasing substantially for American Indians and Alaska Natives. Maternal mortality rates for Black women were the highest of any group, but state-level average rates had begun to plateau around 2015 (pre-COVID) for Black women. Factors such as structural racism and interpersonal racism influence these disparities, Bryant said. Substantial maternal mortality prevention and awareness efforts may have had an impact on some populations, but not all.

Maternal mortality rates and disparities varied widely among states. The South had high maternal mortality across all ethnic and racial groups, but especially for black people. Black people had the highest maternal mortality rates in some northeastern states, which tripled during the time of the study. Maternal mortality rates in the Midwest and Great Plains states were where the highest rates were found for American Indian and Alaska Native women.

"It is often said that Southern states have the worst maternal mortality rates in the country, while California and Massachusetts have the best. But that doesn’t tell the whole story," Bryant said. "It is essential to look at the disparities between populations that exist even in the ’best’ states."

The study had several limitations . Researchers did not always have access to information on the causes of maternal death. And the way maternal deaths are recorded on death certificates has changed in the US during the time of this study.

The data used in the study stopped before the pandemic in 2019. National data shows that maternal mortality increased in 2020 and 2021 when it was more difficult to access health care. The pandemic also hampered some prevention efforts to decrease deaths of Black women. The pandemic may have widened the disparities seen in this study, Bryant said.

“Our findings provide important information about maternal mortality rates leading up to the pandemic, and we are likely to see a continued increase in the risk of maternal mortality across populations if we look at data from subsequent years,” Bryant said. “Black people probably still have the highest rate, but there may have been a larger increase in some of the other groups in recent years. “As we emerge from the pandemic, we must renew our approach to addressing maternal mortality.”

Reference : Fleszar LG et al. " Trends in state-level maternal mortality by race/ethnicity group in the United States, 1999-2019 " JAMA DOI: 10.1001/jama.2023.9043

Funding : This study was supported in part by grants from the National Heart, Lung, and Blood Institute (R01HL136868), the National Institutes of Health (75N94019C00016), and Gates Ventures LLC.