case study of maternal deaths

• Introduction
• Conclusions
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Q indicates quarter.

The 2021 US maternal mortality rate is more than 10 times the rate of other high-income countries, according to a March 2023 CDC report. In this Q&A, JAMA Editor in Chief Kirsten Bibbins-Domingo, PhD, MD, MAS, is joined by Monica McLemore, PhD, MPH, RN, University of Washington, Audra Meadows, MD, MPH, UC San Diego, and Joia Crear-Perry, MD, founder and president of the National Birth...

eTable 1.  ICD-9-CM and ICD-10-CM Diagnosis and Procedure Codes Used for Patient Inclusion and Exclusion

eTable 2.  ICD-9-CM and ICD-10-CM Diagnosis and Procedure Codes Used to Identify Severe Maternal Morbidities

eTable 3.  ICD-9-CM and ICD-10-CM Diagnosis Codes Used to Identify Maternal Comorbidities

eTable 4. Rates of Adjusted Mortality for American Indian Patients with 95% Poisson CIs

Data Sharing Statement

• US Maternal Mortality Is Unacceptably High, Unequal, and Getting Worse—What Can Be Done About It? JAMA Medical News & Perspectives July 25, 2023 This Medical News article is an interview by JAMA Editor in Chief Kirsten Bibbins-Domingo, PhD, MD, MAS, about maternal deaths and disparities in the US. Jennifer Abbasi

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Fink DA , Kilday D , Cao Z, et al. Trends in Maternal Mortality and Severe Maternal Morbidity During Delivery-Related Hospitalizations in the United States, 2008 to 2021. JAMA Netw Open. 2023;6(6):e2317641. doi:10.1001/jamanetworkopen.2023.17641

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Trends in Maternal Mortality and Severe Maternal Morbidity During Delivery-Related Hospitalizations in the United States, 2008 to 2021

• 1 Office on Women’s Health, US Department of Health & Human Services, Washington, DC
• 2 Premier Inc, Charlotte, North Carolina
• 3 Now with Office on Women’s Health, US Department of Health & Human Services, Washington, DC
• 4 Now with Attentive Mobile, New York, New York
• Medical News & Perspectives US Maternal Mortality Is Unacceptably High, Unequal, and Getting Worse—What Can Be Done About It? Jennifer Abbasi JAMA

Question   What were trends of and risk factors associated with maternal mortality and severe maternal morbidity (SMM) among women giving birth in US hospitals during 2008 to 2021?

Findings   In this cross-sectional study of more than 11.6 million delivery-related hospitalizations, regression-adjusted in-hospital maternal delivery-related mortality per 100 000 discharges declined from 10.6 to 4.6, while the prevalence of SMM per 10 000 discharges increased from 146.8 to 179.8 during 2008 to 2021. Differences were found across racial and ethnic groups, age, mode of delivery, and comorbidities for mortality and SMM.

Meaning   In this study, in-hospital maternal mortality improved between 2008 and 2021 despite increases in SMM prevalence and presence of comorbidities for the overall population.

Importance   Maternal mortality and severe maternal morbidity (SMM) are important focus areas in public health. Further understanding trends, health disparities, and risk factors for these adverse outcomes is vital to public health decision-making.

Objective   To describe trends and risk factors for delivery-related maternal deaths and SMM in the United States.

Design, Setting, and Participants   This is a retrospective cross-sectional study using data from a large, geographically diverse, all-payer hospital administrative database. Hospital discharges from January 2008 to December 2021 with any Medicare Severity Diagnosis Related Group, International Classification of Diseases, Ninth Revision, Clinical Modification , or International Classification of Diseases, Tenth Revision, Clinical Modification delivery diagnosis or procedure code were included. Data analysis took place from February 2021 to March 2023.

Exposures   Year, quarter (Q), age, race and ethnicity, delivery method.

Main Outcomes and Measures   Maternal mortality, SMM during delivery-related hospitalization.

Results   Overall, 11 628 438 unique hospital discharges were analyzed, with a mean (SD) age of 28 (6) years. There were 437 579 (3.8%) Asian, 92 547 (0.8%) American Indian, 1 640 355 (14.1%) Black, 1 762 392 (15.2%) Hispanic, 83 189 (0.7%) Pacific Islander, and 6 194 139 (53.3%) White patients. Regression-adjusted maternal mortality per 100 000 discharges declined from 10.6 deaths in Q1 2008 to 4.6 deaths in Q4 2021. Mortality was significantly higher among patients with advanced maternal age (eg, age 35-44 years vs 25-34 years: adjusted odds ratio [aOR], 1.49; 95% CI, 1.22-1.84). Other significant risk factors for mortality included cesarean delivery, comorbid conditions, complications, and COVID-19 diagnosis (eg, cesarean delivery: aOR, 2.28; 95% CI, 1.87-2.79). The prevalence of any SMM increased from 146.8 per 10 000 discharges in Q1 of 2008 to 179.8 per 10 000 discharges in Q4 of 2021. SMM risk factors included age 24 years or younger or age 35 years or older, belonging to a racial or ethnic minority group, cesarean delivery, Medicaid insurance, and having 1 or more comorbidities (eg, age 10-19 years: aOR, 1.39; 95% CI, 1.36-1.42).

Conclusions and Relevance   This cross-sectional study found that delivery-related mortality in US hospitals decreased for all racial and ethnic groups, age groups, and modes of delivery during 2008 to 2021, likely demonstrating the impact of national strategies focused on improving maternal quality of care provided during delivery-related hospitalizations. SMM prevalence increased for all patients, with higher rates for racial and ethnic minority patients of any age. Advanced maternal age, racial or ethnic minority group status, cesarean delivery, and comorbidities were associated with higher odds of mortality and SMM.

Complications from pregnancy and childbirth are leading contributors to mortality and severe morbidities, resulting in significant burden on pregnant patients and their babies. Among developed countries, the United States has the highest maternal mortality ratio. 1 In 2019, there were 3 747 540 births in the United States, with an estimated birth rate of 11.4 per 1000 population. 2 According to US Pregnancy Mortality Surveillance System (PMSS) data, the pregnancy-related mortality ratio in the United States had increased since 1987 from 7.2 deaths per 100 000 live births to 17.3 deaths per 100 000 live births in 2017, although the trend slowed substantially after 2008. 3

Maternal mortality has been described as the “tip of the iceberg” and maternal morbidity as a larger problem, “the base.” 4 For every individual who dies as a result of their pregnancy, it is estimated that 20 or 30 more experience significant lifelong complications that affect their health and well-being. 5 , 6 Severe maternal morbidity (SMM), which the US Centers for Disease Control and Prevention (CDC) defines as “unexpected outcomes of labor and delivery that result in significant short- or long-term consequences to a woman’s health,” 1 has steadily increased in the United States in recent years and is estimated to affect more than 50 000 patients annually.

Causes of maternal deaths and SMM at the time of delivery are multifactorial and are not well documented. 7 Measuring specific outcomes occurring during delivery and hospitalization could improve understanding of how to predict, manage, and mitigate maternal outcomes. In addition, enhanced understanding of the causes of delivery-related death and SMM can inform potential strategies to improve overall maternal health outcomes in the United States. This study aimed to provide evidence to enhance understanding of patterns, trends, and risk factors associated with delivery-related deaths and SMM in US hospitals using a large maternal sample in the hospital setting.

This retrospective cross-sectional study was conducted to examine trends associated with delivery-related maternal in-hospital mortality and SMM between January 2008 and December 2021, using data from the Premier PINC AI Healthcare Database (PHD). All data were statistically deidentified and adherent to the Health Insurance Portability and Accountability Act. Based on US Title 45 Code of Federal Regulations, Part 46, this study was exempted from institutional review board approval and informed consent. The study followed the Strengthening the Reporting of Observational Studies in Epidemiology ( STROBE ) reporting guideline.

The PHD is a large, all-payer (including Medicaid), geographically diverse administrative database comprising more than 1200 US hospitals and health systems. 8 This database represents approximately 25% of all US inpatient admissions. All data were validated at both facility and patient levels. The CDC, the National Institute of Health, and academic and industry researchers have used PHD data for studies in a variety of disease areas. 9 - 15

This study reviewed inpatient hospitalizations between January 1, 2008, and December 31, 2021, with any Medicare Severity Diagnosis Related Group (MS-DRG) or International Classification of Diseases, Ninth Revision, Clinical Modification ( ICD-9-CM ) diagnosis or procedure codes (on or before September 30, 2015) or International Classification of Diseases and Related Health Problems, Tenth Revision, Clinical Modification ( ICD-10-CM ) codes (on or after October 1, 2015) indicating delivery (eTable 1 in Supplement 1 ). Hospitalizations for patients younger than 10 years at time of admission and those with evidence of abortive outcomes were excluded from the study. The index date was defined as the discharge date for the qualifying hospitalization. Missing data for categorical variables were included in the other or unknown group. Only a small percentage of patients had missing data, which should not have affected the trend analysis.

Complications or procedures indicative of SMMs were examined during the delivery-related hospitalization; these included acute myocardial infarction, acute kidney failure, amniotic fluid embolism, aneurysm, cardiac arrest or ventricular fibrillation, cardioversion, disseminated intravascular coagulation, eclampsia, heart failure or arrest during procedure, puerperal cerebrovascular disorders, acute heart failure or pulmonary edema, severe anesthesia complications, sepsis, shock, sickle cell anemia with crisis, air and thrombotic embolism, blood transfusion, hysterectomy, temporary tracheostomy, and ventilation. The diagnosis and procedure codes to identify the complications are listed in eTable 2 in Supplement 1 . The presence of any SMM was used as a measure for the adverse event occurring during delivery. Morbidities were reported as number of patients with each SMM or any SMM of interest per 10 000 eligible discharges.

Death was defined as having delivery-related hospitalization discharge status as deceased. In-hospital mortality was reported as the number of patients who died during index hospitalization per 100 000 eligible discharges.

Patient characteristics included age (10-19, 20-24, 25-34, 35-44, ≥45 years), race and ethnicity (categorized as American Indian, Asian, Black, Hispanic, Pacific Islander, White, and other or unknown), and primary insurance payer. The other or unknown category captures all patients who selected other category for race, had missing data for race or ethnicity, or had a hospital-reported race that could not be matched to the standard race categories used in this article. Race and ethnicity were reported by the hospital. For the purposes of this study, we defined racial or ethnic minority patients as those with race or ethnicity classifications other than White. Hospital characteristics included population served (urban, rural), teaching status, US census divisions (ie, Middle Atlantic, Mountain, East North Central, East South Central, New England, Pacific, South Atlantic, West North Central, and West South Central), and hospital size (1-299, 300-499, and ≥500 beds). Visit information, such as index year, quarter (Q), admission type (elective, emergency, urgent, or trauma center), and an indicator for pre– ICD-10-CM or post– ICD-10-CM coding system change on October 1, 2015, were also examined.

The individual conditions in the Maternal Comorbidity Index (MCI) 16 were assessed as potential risk factors of maternal mortality or morbidity, including pulmonary hypertension, placenta previa, sickle cell disease, gestational hypertension, mild or unspecified preeclampsia, severe preeclampsia, chronic kidney disease, preexisting hypertension, chronic ischemic heart disease, congenital heart disease, systemic lupus erythematosus, HIV, multiple gestation, substance use disorder, alcohol abuse, tobacco use, cardiac valvular disease, chronic congestive heart failure, asthma, preexisting diabetes, gestational diabetes, obesity, cystic fibrosis, and previous cesarean delivery (eTable 3 in Supplement 1 ). The type of delivery (vaginal, cesarean) and COVID-19 status were also examined.

All SMMs were included as covariates for the mortality analysis. Because of overlap across comorbid conditions, certain SMMs were grouped together. Per CDC recommendations, cardiac conditions (including acute myocardial infarction, cardiac arrest or ventricular fibrillation, conversion of cardiac rhythm, heart failure or arrest during surgery or procedure, and pulmonary edema or acute heart failure) were grouped into 1 binary variable called cardiovascular complications for multivariable modeling. Acute respiratory conditions (including acute respiratory distress syndrome, temporary tracheostomy, and ventilation) were grouped into a binary variable called respiratory complications. 17 Hemorrhage and blood transfusion were combined into bleeding complications with 3 categories: no bleeding, hemorrhage with no blood transfusion, and blood transfusion. Eclampsia, severe preeclampsia without eclampsia, mild or unspecified preeclampsia without eclampsia, or severe preeclampsia, and no preeclampsia or eclampsia were grouped into one 4-level covariate.

Descriptive analysis was performed to assess the distribution of demographics and hospital and clinical characteristics for each year. Categorical variables were expressed as counts and percentages. Owing to space limitations, we only included specific descriptive results for 2008, 2014 (ie, the year before the ICD-9-CM to ICD-10-CM coding change), 2016 (ie, the year after the ICD-9-CM to ICD-10-CM coding change), 2019 (ie, the year before the COVID-19 pandemic), 2020, and 2021 (ie, years during the COVID-19 pandemic), rather than for all years in this study.

Two separate multivariable logistic regression models were created to assess the independent associations of potential risk factors with delivery-related maternal mortality and SMM, adjusting for confounders. For both models, patient demographics, hospital and visit characteristics, and MCI conditions were included as covariates. In the mortality regression, the SMM complications were added to the model to account for disease conditions that happened during the delivery-related hospitalization before the occurrence of mortality. In addition, a logistic regression of mortality without SMMs as covariates was performed as a sensitivity analysis. Backward selection with P  < .05 was used to select final models, with the exception that patient age, race and ethnicity, delivery type, and study year and Q were kept in the model regardless of P values. For the mortality model, SMM conditions that were closely related to each other were combined. Combined variables included bleeding complications, cardiovascular complications, respiratory complications, and an eclampsia or preeclampsia category. In the regression of SMM, eclampsia was 1 component of the SMM outcome, while the preeclampsia conditions were used as separate covariates in the model.

Adjusted mortality and SMM rates for the overall study population were calculated using recycled prediction methods 16 , 18 based on estimates from the regressions. Adjusted mortality and SMM rates were also reported by age group, race and ethnicity, and type of delivery, based on additional regression models that included interaction terms between year and the variable of interest.

All analyses were conducted using Python Scikit-Learn package version 0.22.1 (Python Software Foundation). Analysis of the data took place from February 2021 through March 2023. P values were 2-sided, and statistical significance was set at P  < .05.

Among the 11 628 438 eligible discharges related to delivery, more than half (6 498 217 [55.9%]) were among patients aged 25 to 34 years, 1 885 571 (16.2%) were among patients aged 35 years or older, and 759 301 (6.5%) were among patients aged 10 to 19 years. There were 437 579 (3.8%) Asian patients, 92 547 (0.8%) American Indian patients, 1 640 355 (14.1%) Black patients, 1 762 392 (15.2%) Hispanic patients, 83 189 (0.7%) Pacific Islander patients, and 6 194 139 (53.3%) White patients. Medicaid was identified as the primary payer for 4 958 174 discharges (42.6%). The census region distribution reflected the geographic distribution of the PHD patient population. Approximately one-third of the sample underwent cesarean delivery. The proportion of discharges in younger age groups decreased while the proportion in older age groups increased over the study period. The distribution of race and ethnicity, primary payer type, census region, and delivery type did not differ significantly across years ( Table 1 ).

As shown in Table 1 , obesity (91.0 per 1000 discharges), gestational diabetes (74.3 per 1000 discharges), and tobacco use (58.2 per 1000 discharges) were the most common comorbidities, followed by gestational hypertension, asthma, preeclampsia, preexisting hypertension, and substance use disorder. Compared with the prevalence in 2008, higher prevalence of sickle cell disease, gestational hypertension, severe preeclampsia, preexisting hypertension, substance use disorder, asthma, gestational diabetes, obesity, and hemorrhage were observed in 2021 ( Table 1 ).

The unadjusted prevalence of any SMM was estimated to be 163.3 per 10 000 discharges for the overall sample from 2008 to 2021, with higher prevalence observed in 2021 (206.1 per 10 000 discharges) compared with 2008 (135.2 per 10 000 discharges). Blood transfusion was the most common SMM observed, with a prevalence of 108.4 per 10 000 discharges. Other relatively common SMMs included disseminated intravascular coagulation (24.7 per 10 000 discharges), hysterectomy (11.0 per 10 000 discharges), acute respiratory distress syndrome (9.8 per 10 000 discharges), acute kidney failure (9.7 per 10 000 discharges), sepsis (7.4 per 10 000 discharges), eclampsia (7.2 per 10 000 discharges), shock (6.1 per 10 000 discharges), and acute heart failure or pulmonary edema (5.6 per 10 000 discharges). Prevalence of acute kidney failure, acute respiratory distress syndrome, sepsis, shock, mechanical ventilation, blood transfusion, and hysterectomy were higher in 2021 than in 2008 ( Table 1 ).

As seen in Figure 1 A, the adjusted prevalence of any SMM increased from Q1 2008 (146.8 per 10 000 discharges) to Q4 2021 (179.8 per 10 000 discharges). The increasing trend was observed in all age groups with the greatest change observed in patients aged 45 years or older and those aged 10 to 19 years ( Figure 1 B). Consistent increasing trend was also observed in all racial and ethnic groups, with the biggest increase observed among Pacific Islander patients (from 132.0 per 10 000 discharges in Q1 2008 to 298.8 per 10 000 discharges in Q4 2021), American Indian patients (from 156.5 per 10 000 discharges in Q1 2008 to 245.0 per 10 000 discharges in Q4 2021), and Asian patients (from 133.4 per 10 000 discharges in Q1 2008 to 238.2 per 10 000 discharges in Q4 2021) ( Figure 1 C). A significant increase in adjusted SMM prevalence was observed in patients undergoing cesarean delivery (from 252.4 per 10 000 discharges in Q1 of 2008 to 312.1 per 10 000 discharges in Q4 of 2021), and a similarly increasing trend was seen in patients with vaginal delivery (from 84.4 per 10 000 discharges in Q1 of 2008 to 108.4 per 10 000 discharges in Q4 of 2021) ( Figure 1 D).

As shown in Figure 2 A, a downward trend was observed for in-hospital mortality among deliveries after adjusting for changes in patient demographic, visit, hospital, and clinical characteristics. From Q1 of 2008 to Q4 of 2021, the adjusted in-hospital mortality decreased from 10.6 per 100 000 discharges to 4.6 per 100 000 discharges. Each subsequent year after 2008 had an 11% decrease in odds of death compared with the previous year (adjusted odds ratio [aOR], 0.89; 95% CI, 0.87-0.92) ( Table 2 ). There was an increase in mortality from Q2 of 2020 through Q4 of 2021 that may be associated with the COVID-19 pandemic. However, after controlling for COVID-19 diagnosis, the adjusted trend decreased consistently across the full study period. The downward trend for in-hospital mortality was observed in all age groups, with the biggest decrease occurring in patients aged 45 years or older ( Figure 2 B). A decreasing trend for in-hospital mortality was observed in all racial and ethnic groups. In particular, the greatest decrease in adjusted mortality was observed for American Indian patients: from 34.8 per 100 000 discharges in Q1 of 2008 to 2.7 per 100 000 discharges in Q4 of 2021 ( Figure 2 C; the 95% CI for mortality among American Indian patients is provided in eTable 4 in Supplement 1 ). In-hospital mortality consistently decreased during the study period for patients with cesarean delivery (from 12.6 per 100 000 discharges in Q1 of 2008 to 5.2 per 100 000 discharges in Q4 of 2021) and also for patients with vaginal delivery (from 6.6 per 100 000 discharges in Q1 of 2008 to 3.0 per 100 000 discharges in Q4 of 2021) ( Figure 2 D).

Compared with patients aged 25 to 34 years, those between 35 and 44 years had higher odds of dying during the index hospitalization (aOR, 1.49; 95% CI, 1.22-1.84). Although the association between race and mortality was not statistically significant in the regression in which SMMs were included as covariates, a sensitivity analysis showed that American Indian (aOR, 1.93, 95% CI, 1.10-3.39), Black (aOR, 1.78; 95% CI, 1.47-2.15), and Asian patients (aOR, 1.61, 95% CI, 1.11-2.34) had increased risk of death compared with White patients, suggesting that the racial disparity was partly attributable to the difference in the SMM rates across racial and ethnic groups. The mortality of Pacific Islander patients and Hispanic patients was not statistically significantly different from White patients in the sensitivity analysis. Patients with cesarean delivery had 2-fold higher odds of death than those with vaginal delivery (aOR, 2.28; 95% CI, 1.87-2.79). Patients with a COVID-19 diagnosis had a 13-fold increased odds of mortality compared with those without COVID-19 (aOR, 13.31; 95% CI, 8.95-19.79). Among comorbidity and acute complications assessed, cardiac complications, cystic fibrosis, aneurysm, trauma, and puerperal cerebrovascular disorder were among the risk factors associated with death during delivery-related hospitalization ( Table 2 ).

As seen in Table 2 , after adjusting for other risk factors and compared with patients aged 25 to 34 years, both patients younger than 24 years (eg, age 10-19 years: aOR, 1.39; 95% CI, 1.36-1.42) and older than 35 years (eg, age ≥45 years: aOR, 1.76; 95% CI, 1.65-1.88) had increased odds of SMM. All minority racial and ethnic groups were associated with increased odds of experiencing any SMM (Pacific Islander: aOR, 1.53; 95% CI, 1.45-1.61; American Indian: aOR, 1.41; 95% CI, 1.35-1.48; Black: aOR, 1.39; 95% CI, 1.38-1.41; Asian: aOR, 1.33; 95% CI, 1.30-1.36; Hispanic: aOR, 1.22; 95% CI, 1.20-1.24). Cesarean delivery (aOR, 3.00; 95% CI, 2.97- 3.03) and COVID-19 diagnosis (aOR, 4.44; 95% CI, 4.23-4.66) were also associated with substantially higher adjusted odds of SMM. Among all the chronic comorbidities assessed, placenta previa (aOR, 6.32; 95% CI, 6.17-6.47), chronic kidney disease (aOR, 5.21; 95% CI, 4.99-5.44), severe preeclampsia (aOR, 4.55; 95% CI, 4.48-4.62), cardiac valvular disease (aOR, 3.50; 95% CI, 3.32-3.69), chronic ischemic heart disease (aOR, 3.92; 95% CI, 3.50-4.39), and sickle cell disease (aOR, 2.93; 95% CI, 2.82-3.05) were associated with the highest odds of experiencing SMM ( Table 2 ).

This cross-sectional study examined rates of delivery-related in-hospital maternal mortality and SMM in a large national inpatient database. In this sample encompassing more than 11 million inpatient discharges, delivery-related in-hospital mortality was found to decrease significantly over a period of 14 years. The adjusted mortality per 100 000 discharges decreased by more than 50% from Q1 of 2008 to Q4 of 2021, likely demonstrating the impact of national strategies focused on improving the maternal quality of care provided by the hospitals during delivery-related hospitalizations. In contrast, the rates of overall SMM increased over time for the overall population, which may be attributable to preexisting conditions and the increasing trend in the age of delivering patients in the past decade. The increasing trend of adjusted SMM rates was seen in all racial and ethnic minority groups and was most prominent in Asian, American Indian, and Pacific Islander patients. The fact that many of the comorbid conditions are risk factors for mortality and SMM indicates that it is essential to consider comorbid conditions when assessing SMM and mortality and that better management of patients’ comorbid conditions during pregnancy may help reduce SMM occurrence and ultimately decrease mortality risk. Further improvement in patient outcomes could be achieved if patients with known risk factors could access improved care during pregnancy and during hospital delivery.

Delivery-related in-hospital maternal mortality in this study was lower than that reported in PMSS data, which defined pregnancy-related death as death during pregnancy or within 1 year of the end of pregnancy, from a cause related to pregnancy or its management. 3 PMSS data showed an increasing trend in pregnancy-related mortality during 1987 to 2017, which differs from our findings. A plausible explanation for these differences is that the timeframe for assessing mortality was substantially different between our study and the PMSS. Our study focused on mortality during delivery-related hospitalizations, which was associated with the change in quality of care for all patients in a hospital setting. In contrast, the PMSS estimates cover the entire pregnancy and postpartum period, which are associated with the overall burden of deaths among pregnant patients. Because a proportion of pregnancy-related deaths occur during delivery hospitalization, the differences between our findings and the PMSS estimates reinforced the importance of examining mortality separately for different stages of pregnancy and postpartum.

The study found that mortality risk was associated with several factors, including advanced maternal age, Medicaid as primary insurance, cesarean delivery, comorbid conditions, and severe complications during delivery. Similarly, a maternal age younger than 19 years or older than 35 years; being Asian, American Indian, Black, Hispanic, Pacific Islander; cesarean delivery; Medicaid enrollment; and maternal comorbid conditions were associated with higher risk of developing SMM during delivery. The racial and ethnic differences observed in delivery-related maternal mortality seem to be at least partly attributable to the racial and ethnic variation observed in SMM based on the main and sensitivity analyses of this study. Therefore, further research and understanding on the causes of both mortality and SMM, including the impact of comorbidities on maternal outcomes, is needed. Additionally, developing a national hospital measure to more clearly identify and reduce SMMs will likely have a beneficial impact on improving national quality strategies aimed at improving maternal health outcomes in the United States.

The study has limitations. The PHD is a hospital administrative database and does not include as much clinical details as electronic health records. Identifying clinical conditions and procedures relied on the accuracy of hospital-reported diagnosis and procedure codes. Coding errors may lead to misclassification of variables. The definition of mortality was based on in-hospital death during the visit for delivery, without accounting for death before delivery admission or after discharge.

Maternal comorbid conditions were defined based on diagnosis during the visit for delivery. Conditions occurring before admission may not have been captured. Since the study spanned 14 years, there were changes in how hospitals collected and reported race and ethnicity. Hispanic was reported as a race category before 2011, while ethnicity was listed as a separate field in the patient admission form in later years. Hispanic race or ethnicity as defined in this study included patients who reported Hispanic as their race before 2011 and those who reported Hispanic as their ethnicity in 2012 and later, regardless of their reported race.

This large national study found a decreasing trend of in-hospital delivery-related maternal mortality during 2008 to 2021, regardless of racial or ethnic group, age, or mode of delivery, likely demonstrating the impact of national and local strategies focused on improving the maternal quality of care provided by hospitals during delivery-related hospitalizations. Risk factors for in-hospital delivery-related mortality included cesarean delivery, COVID-19 diagnosis, and comorbidities and acute complications. Analysis indicated that American Indian, Black, and Asian patients had a statistically significant increased risk of death compared with White patients only when not controlling for SMMs, suggesting that the racial difference in mortality could be at least partly attributable to the differences in SMM rates across racial groups (analysis of Pacific Islander and Hispanic patients were not statistically significant).

From 2008 to 2021, there was an increasing trend of SMM rates, and chronic comorbid conditions were associated with higher rates. SMMs are known risk factors of maternal deaths and impose substantial social and economic burdens. Notably, disparities in both mortality and SMM remained across age, delivery mode, and racial and ethnic groups. These characteristics should be considered when designing maternal care quality improvement programs. As current national strategies increasingly focus on improving delivery-related maternal outcomes among high-risk groups, including racial and ethnic minority groups, it will become important to evaluate the effectiveness of these strategies in reducing occurrences of maternal mortality and SMM.

Accepted for Publication: April 12, 2023.

Published: June 22, 2023. doi:10.1001/jamanetworkopen.2023.17641

Open Access: This is an open access article distributed under the terms of the CC-BY License . © 2023 Fink DA et al. JAMA Network Open .

Corresponding Authors: Dorothy A. Fink, MD ( [email protected] ), and Deborah Kilday ( [email protected] ), US Department of Health & Human Services, 1101 Wootton Pkwy, Rockville, MD 20852.

Author Contributions: Messers Lipkin and Perigard had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Fink, Kilday, Cao, Larson, Smith, Perigard, Marshall, Deirmenjian, Rosenthal.

Acquisition, analysis, or interpretation of data: Fink, Kilday, Cao, Larson, Smith, Lipkin, Perigard, Finke, Tatum, Deirmenjian, Rosenthal.

Drafting of the manuscript: Fink, Kilday, Cao, Smith, Perigard, Tatum, Deirmenjian, Rosenthal.

Critical revision of the manuscript for important intellectual content: Fink, Kilday, Cao, Larson, Smith, Lipkin, Perigard, Marshall, Finke, Deirmenjian, Rosenthal.

Statistical analysis: Kilday, Cao, Lipkin, Tatum, Deirmenjian, Rosenthal.

Obtained funding: Kilday, Marshall.

Administrative, technical, or material support: Kilday, Larson, Smith, Marshall, Finke, Deirmenjian, Rosenthal.

Supervision: Kilday, Smith, Marshall, Deirmenjian, Rosenthal.

Conflict of Interest Disclosures: Ms Kilday, Dr Cao, Ms Larson, Mr Lipkin, Mr Perigard, Ms Finke, Mr Tatum, Ms Deirmenjian, and Dr Rosenthal reported having a contract with the Department of Health and Human Services Maternal Morbidity and Mortality Data and Analysis Project during the conduct of the study and outside the submitted work. No other disclosures were reported.

Funding/Support: This project was supported by the US Department of Health & Human Services Office on Women’s Health (contract No. 75P00120C00066).

Role of the Funder/Sponsor: Under the leadership of the HHS Office on Women’s Health team, this study was designed and conducted; data were collected, managed, analyzed, and interpreted; the manuscript was prepared, reviewed, and approved; and decision to submit the manuscript for publication was made.

Disclaimer: The opinions expressed in this article are the authors’ own and do not reflect the view of the Department of Health and Human Services.

Data Sharing Statement: See Supplement 2 .

Additional Contributions: Margaret Snyder, MALD, and Alain Moluh, MSc (Department of Health and Human Services); and Amy Karon, DVM, MPH, MA, and Cate Polacek, MLIS (Premier, Inc), assisted with manuscript editing. Alex Kartashov, PhD, MS, Ben Davis, MS, Antony Vibin, BS, Himanshu Jayswal, MS (Premier, Inc), assisted with conducting statistical analyses and generating descriptive tables. Ashley Wilkes, BS (Premier Inc), assisted with project management, manuscript revision, and analysis and technology support.

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Maternal Mortality in the United States: Updates on Trends, Causes, and Solutions

Ai-ris y. collier.

* Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, MA

‡ Harvard Medical School, Boston, MA

Rose L. Molina

† Division of Global and Community Health, Department of Obstetrics and Gynecology, Beth Israel Deaconess Medical Center, Boston, MA

The rising trend in pregnancy-related deaths during the past 2 decades in the United States stands out among other high-income countries where pregnancy-related deaths are declining. Cardiomyopathy and other cardiovascular conditions, hemorrhage, and other chronic medical conditions are all important causes of death. Unintentional death from violence, overdose, and self-harm are emerging causes that require medical and public health attention. Significant racial/ethnic inequities exist in pregnancy care with non-Hispanic black women incurring 3 to 4 times higher rates of pregnancy-related death than non-Hispanic white women. Varied terminology and lack of standardized methods for identifying maternal deaths in the United States have resulted in nuanced data collection and interpretation challenges. State maternal mortality review committees are important mechanisms for capturing and interpreting data on cause, timing, and preventability of maternal deaths. Importantly, a thorough standardized review of each maternal death leads to recommendations to prevent future pregnancy-associated deaths. Key interventions to improve maternal health outcomes include 1) integrating multidisciplinary care for women with high-risk comorbidities during preconception care, pregnancy, postpartum, and beyond; 2) addressing structural racism and the social determinants of health; 3) implementing hospital-wide safety bundles with team training and simulation; 4) providing patient education on early warning signs for medical complications of pregnancy; and 5) regionalizing maternal levels of care so that women with risk factors are supported when delivering at facilities with specialized care teams.

INTRODUCTION

Maternal death during pregnancy, childbirth, or postpartum is a tragedy with catastrophic impact on families and serves as an important indicator of the quality of a health system. The World Health Organization (WHO) has defined maternal mortality ratio (MMR) as “the number of maternal deaths per 100,000 live births, [where] maternal death is the death of a woman while pregnant or within 42 days of termination of pregnancy,” regardless of whether the cause was related to or aggravated by pregnancy. ( 1 ) However, according to the WHO definition, maternal deaths do not include those from accidental or incidental causes. Although the MMR has been the most common indicator for international comparisons of maternal health, it does not specify the cause of death in relation to pregnancy.

The MMR in the United States has decreased drastically in the last century because of advances in surgical technique, safer anesthesia, antisepsis, and overall improved living conditions. Although the MMR dropped from 900 deaths per 100,000 live births in the 1900s to 12.7 in 2007, the US rate of MMR has seen a rise over the past several decades. ( 2 ) In 2014, complications during pregnancy, childbirth, and the postpartum period ranked as the 6th greatest cause of death among women aged 20 to 34 in the United States. ( 3 ) The MMR in the United States has more than doubled from 9.8 per 100,000 live births in 2000 to 21.5 in 2014, ( 4 ) and this trend stands out among high-income countries; maternal mortality has decreased in other high-income countries, such as Canada and the United Kingdom, during the same time period. According to the WHO, the MMR has fallen by 44% from 1990 to 2015 in low- and middle-income countries. ( 5 )

When interpreting these trends, however, we must also account for improvements in data ascertainment. The addition of a pregnancy question on the US death certificate in 2003 coincided with increased mortality rate, which suggests improved detection and reporting as part of the story. ( 4 ) Increasing maternal mortality rates vary by state and have generated public attention on family planning availability and the growing prevalence of chronic medical conditions including obesity, diabetes, and heart disease. Delayed childbearing leading to more advanced age during pregnancy, higher cesarean delivery rates, the opioid epidemic, and fragmented and limited access to care during and after pregnancy have also been identified as potential contributors. ( 6 )

In the United States, the racial/ethnic inequities in maternal deaths are troubling; most notably, non-Hispanic black women carry a 3- to 4-fold risk of pregnancy-related deaths compared with non-Hispanic white women. ( 7 ) While the medical and public health communities have made strides to reduce infant mortality with strategies such as the Safe to Sleep campaign, ( 8 ) it is time to focus on solutions to improve maternal health as well, particularly for those at highest risk for adverse outcomes. This review summarizes the data collection challenges, causes of maternal mortality and severe maternal morbidity, inequities in maternal health outcomes, and solutions to reduce maternal morbidity and mortality.

DEFINITIONS AND DATA COLLECTION CHALLENGES

In the United States, the Centers for Disease Control and Prevention (CDC) has put forward 3 classifications of pregnancy-associated death (death of a woman while pregnant or within 1 year of termination of pregnancy, irrespective of the cause)( 9 ):

• Pregnancy-related: “The death of a woman while pregnant or within 1 year of termination of pregnancy, from any cause related to or aggravated by her pregnancy or its management, but not from accidental or incidental causes.” (Example: the death of a woman from postpartum hemorrhage or amniotic fluid embolism).
• Pregnancy-associated but not pregnancy-related: “The death of a woman while pregnant or within 1 year of termination of pregnancy due to a cause unrelated to pregnancy.” (Example: the death of a pregnant woman from an earthquake).
• Pregnancy-associated but undetermined if pregnancy-related: “The death of a woman while pregnant or within 1 year of termination of pregnancy from a cause that cannot be determined or conclusively categorized as either pregnancy-related or not pregnancy related.” (Example: a woman with an unknown mental health history dies at 6 months postpartum from a self-inflicted cause).

The CDC manages the 2 national data sources of maternal deaths: 1) the National Vital Statistics System compiled annually by the National Center for Health Statistics (NCHS), and 2) the Pregnancy Mortality Surveillance System (PMSS), a flagship program run by the Division of Reproductive Health at the National Center for Chronic Disease Prevention and Health Promotion ( Table ). ( 10 ) The NCHS relies exclusively on International Classification of Diseases, 10th Revision (ICD-10) codes assigned to causes of death listed on maternal death certificates and publishes the maternal mortality rate, consistent with the WHO definition of maternal death. The PMSS relies on epidemiologists to classify deaths according to the aforementioned definitions of pregnancy-related and pregnancy-associated deaths and allocate the causes of death into 10 categories: hemorrhage, infection/sepsis, amniotic fluid embolism, thrombotic pulmonary or other embolism, hypertensive disorders of pregnancy, anesthesia complications, cerebrovascular accidents, cardiomyopathy, cardiovascular disease, and noncardiovascular medical conditions.

Sources of Maternal Mortality Information in the United States

ICD-10=International Classification of Diseases, 10th Revision.

Adapted from St Pierre et al. ( 80 )

Measurement challenges include the limitations of ICD code accuracy and significant variation in the statewide implementation of the pregnancy checkbox on death certificates, which began in 2003, but was not fully implemented in all states until 2016. ( 10 ) Multiple studies have concluded that improvements in reporting and case ascertainment explain some of the recent increase in maternal mortality in the United States. ( 7 )( 11 )( 12 )( 13 ) One study estimated that about 80% of the reported increase in maternal mortality between 2000 and 2014 could be attributed to improvements in data linkages and the pregnancy box. ( 10 ) Another study found that the addition of the checkbox may have increased case identification but also misclassification, particularly among women aged 40 years or older. ( 14 ) However, after correcting for improved ascertainment of maternal deaths from implementation of the pregnancy question, the adjusted average MMR across 48 US states is still estimated to have risen by 27% from 18.8 to 23.8 per 100,000 live births from 2000 to 2014 ( 4 ); the smaller adjusted increase in MMR is because of significant under-reporting during the early time point. ( 4 ) The MMR in Texas doubled from 2011 to 2014, suggesting gaps in data quality rather than a true doubling of maternal death rates. ( 13 ) The study team used an enhanced method with full review of medical records for identifying pregnancy-associated deaths and found that more than half of the obstetric-coded deaths were inaccurately labeled. ( 13 ) However, even accounting for these data collection challenges, the MMR in the United States has not decreased substantially in the recent decades, as it has in other high-income countries.

State-based maternal mortality review committees (MMRCs) are the gold standard in identifying and reviewing pregnancy-associated and pregnancy-related deaths because they are made of a multidisciplinary team that reviews all available data, including prenatal records, hospital records, and autopsy reports. ( 10 ) MMRCs are now functional in approximately two-thirds of states and are best positioned to classify deaths as preventable or not and to make recommendations to prevent similar deaths in the future. ( 15 )( 16 )( 17 )( 18 )( 19 )( 20 ) The CDC has developed a standardized data collection system for state MMRCs called the Maternal Mortality Review Information Application (MMRIA). ( 21 ) The MMRIA is a publicly available set of standardized forms for abstracting data and recording MMRC decisions on 6 key questions: 1) Was the death pregnancy-related? 2) What was the cause of death? 3) Was the death preventable? 4) What were the factors that contributed to this death? 5) What are the recommendations and actions that address those contributing factors? 6) What is the anticipated impact of those actions if implemented?”( 21 ) MMRCs play a critical role in evaluating all information about maternal deaths to identify systems solutions to improve care delivery for those that are deemed preventable.

CAUSES OF MATERNAL MORTALITY AND MORBIDITY

The 2018 report from 9 state MMRCs concluded that around 50% of all pregnancy-related deaths were caused by hemorrhage, cardiovascular/coronary conditions, cardiomyopathy, or infection. For non-Hispanic black women, the most common underlying causes of death included preeclampsia, eclampsia, and embolism. For non-Hispanic white women, mental health conditions were the leading cause of death. ( 22 )

The most recent CDC report on maternal mortality from May 2019 also identified cardiovascular conditions (including cardiomyopathy, myocardial infarction, and cerebrovascular accidents) as the cause for more than 33% of pregnancy-related deaths ( Fig 1 ). ( 22 )( 23 )( 24 ) From 2003 to 2012 there was a 25% increase in the number of women entering pregnancy with preexisting heart disease. Most of these women have congenital heart disease or valvular heart disease. However, the prevalence of cardiomyopathy and pulmonary hypertension increased significantly and demonstrated the highest in-hospital mortality, most often because of heart failure, arrhythmia, respiratory failure, shock, renal failure, and preeclampsia. ( 25 ) It is unclear why the incidence of cardiomyopathy is increasing, but it could be associated with increases in maternal age, multifetal pregnancies, or improved recognition.

Leading causes of pregnancy-related death, by timing of death. Adapted from Petersen EE, Davis NL, Goodman D,etal. Vital signs: pregnancy-related deaths, United States, 2011–2015, and strategies for prevention, 13 states, 2013–2017. MMWR Morb Mortal Wkly Rep . 2019;68:423–429. Note: Cardiac conditions include both cardiomyopathy and other cardiovascular disease.

In a study of the National Inpatient Sample from 2002 to 2013, the incidence of cardiogenic shock (the most extreme of cardiovascular disease associated with mortality) increased over 3-fold; the mortality rate for pregnant women with cardiogenic shock was 19% compared with 0.02% of women without cardiogenic shock. ( 26 ) More than 80% of pregnant and postpartum women with cardiogenic shock had peripartum cardiomyopathy, a pregnancy-associated diagnosis that has also increased during the same period. ( 27 ) Both acute and chronic renal failure were significantly associated with mortality in women with cardiogenic shock. ( 26 ) Commonly identified risk factors for cardiovascular death include increasing maternal age, obesity, and hypertensive disorders. ( 27 )( 28 ) Strategies aimed at reducing modifiable chronic conditions such as obesity, hypertension, and diabetes in women of reproductive age may help reduce the incidence of cardiovascular disease and major adverse events. In addition, multidisciplinary care of pregnant women with cardiovascular disease, beginning with adequate risk assessment and evaluation for known and unknown cardiac disease is necessary to eliminate preventable maternal deaths. ( 29 )( 30 )( 31 )

Obstetric hemorrhage was the cause of 11.5% of pregnancy-related deaths from 2011 to 2014 and is usually preventable. ( 32 ) Hemorrhage also accounts for the overwhelming majority of severe maternal morbidity, with blood product transfusions rising from 25 per 10,000 delivery hospitalizations in 1993 to 122 per 10,000 delivery hospitalizations in 2014. ( 24 ) This is a critical area for focused efforts to implement hospital-based national safety bundles, multidisciplinary team training, simulation, and reporting systems so that cases can be reviewed to ensure continuous improvement in safety and quality. ( 33 ) Successful implementation of state-wide bundles across 99 diverse hospitals in California has demonstrated reductions in severe morbidity rates from hemorrhage by 20.8%. ( 34 ) Some of the increase in prevalence of hemorrhage can be attributed to skyrocketing rates of cesarean delivery. Although cesarean can be a life-saving intervention, the US average annual cesarean delivery rate has risen from 23% in 1996 to 33% in 2011 without a corresponding reduction in maternal and neonatal morbidity or mortality. ( 35 ) Cesarean delivery is associated with increased maternal mortality and morbidity (particularly hemorrhage, infection, and thromboembolism) compared with vaginal birth and leads to future risks for abnormal placentation such as placenta previa and placenta accreta in subsequent pregnancies. The American College of Obstetricians and Gynecologists (ACOG) has taken steps to reduce the number of unnecessary cesarean deliveries by creating guidelines for the safe prevention of the primary cesarean. ( 35 )

Another important emerging contributor to maternal death is self-harm (suicide or accidental overdose). In Colorado, 30% of the 211 maternal deaths over a 9-year study period were related to self-harm, with the majority occurring in the postpartum period. Prior psychiatric history and psychopharmacotherapy use during pregnancy were documented in over half of these women. ( 36 ) In Philadelphia, over a 4-year period, 49% of maternal deaths had nonmedical causes, including unintentional injury (overdose, motor vehicle crash, or other), homicide, and suicide; overdose composed 40% of nonmedical causes of maternal deaths. ( 37 ) The authors caution againstnarrowing the focus of maternal mortality on medical causes because nonmedical causes, particularly unintentional overdose, are important contributors to pregnancy-associated mortality. Mental illness, substance use, and intimate partner violence are common risk factors among women who died of both medical and nonmedical causes, reinforcing the importance of screening and providing interdisciplinary perinatal management of substance use disorders and psychobehavioral interventions. ( 37 )

Severe maternal morbidity (SMM) is defined by the CDC as an index of 18 indicators of significant events (such as blood transfusion, hysterectomy, heart failure, eclampsia, respiratory distress, and sepsis) corresponding to ICD-10 diagnoses during delivery admission. ( 24 ) These indicators were chosen because they can be life-threatening, and are associated with short- or long-term morbidity, prolonged hospitalization, and high health care costs. ( 2 ) Many studies of smaller datasets use SMM as a surrogate for maternal mortality because SMM is thought to include the sentinel events that lead to significantly increased risk of death. SMM rates have increased 200% from 1993 to 2014, and this increase is primarily driven by increasing blood transfusions in response to postpartum hemorrhage. After removing blood transfusion, SMM has increased 20% over this period, with hysterectomy and temporary ventilatory support accounting for the next most common complications. ( 24 )

The prevalence of reproductive-aged women with chronic conditions continues to rise, and pregnant women with multiple chronic conditions are at 276% higher risk of SMM and mortality than women with no chronic conditions. ( 38 ) Women with multiple chronic conditions are often older than women with a single chronic condition or no chronic conditions. Noncardiovascular medical conditions accounted for 14.3% of pregnancy-related deaths during the period from 2011 to 2015. ( 23 )

Prepregnancy obesity has been associated with SMM and mortality in a cohort of women delivering in Washington State between 2004 and 2013, suggesting that the obesity epidemic was an important contributing factor to adverse maternal health outcomes. ( 39 ) An analysis of California births found that the incidence of SMM increased 65% from 2007 to 2014 and the prevalence of prepregnancy obesity, maternal age older than or equal to 35 years, and comorbid conditions also increased during the same period, but were estimated to contribute only 13% of the increasing morbidity. ( 40 ) Cesarean delivery was estimated to contribute 37% of the SMM in California during these 7 years. Increasing prevalence of maternal chronic medical conditions and cesarean delivery accounts for only half of the SMM, leaving room for investigation of other contributing factors. Although national efforts to reduce unnecessary cesarean deliveries may be promising interventions for reducing SMM, this study underscores the need to also address other contributing factors. ( 40 )

In a study using delivery data from Washington State from 2000 to 2008, the rate of early-onset preeclampsia before 34 weeks’ gestation increased by 33% and was associated with a 10-fold greater risk of maternal death compared with women without preeclampsia. ( 41 ) Preeclampsia is also associated with significantly higher rates of SMM, particularly from cardiovascular, respiratory, or renal failure. Hypertensive disease in pregnancy has long-term health implications, including a 2-fold increased risk for all-cause mortality before age 50 years, and increased mortality related to diabetes, ischemic heart disease, and stroke. These long-term sequelae occurred more frequently in the group of women who had 2 or more pregnancies complicated by hypertensive disease. ( 42 ) Identifying women at risk for cardiovascular disease during their childbearing years offers an opportunity to intervene and optimize long-term health.

Access to abortion care has been curtailed in multiple states because of legislative restrictions on physician and facility requirements, medication abortion restrictions, gestational age limits, funding cuts, mandatory waiting periods, and parental consent laws, which can place women at increased risk of harm if they attempt self-induced abortions. ( 43 ) Improved insurance coverage for abortion care through state Medicaid has been associated with 16% fewer cases of SMM, suggesting that increased coverage for abortion care reduces complications associated with pregnancy. ( 44 )

INEQUITIES IN MATERNAL MORBIDITY AND MORTALITY

Inequities—differences that are systematic, avoidable, and unjust—in maternal health outcomes have persisted and are a cause for concern. Although multiple social conditions confer increased risk of adverse outcomes, the most prominent examples of inequities in maternal health in the United States are rooted in the social constructs of race and ethnicity. One conceptual model from Dr Elizabeth Howell demonstrates the ecosystem of factors (patient, community/neighborhood, provider, and systems) that contribute to adverse health outcomes throughout the continuum of reproductive health care, particularly for women of color. ( 45 )

Black women experience maternal deaths at a rate 3 to 4 times that of white women in the United States, ( 2 )( 7 ) regardless of age. ( 46 ) According to the CDC, the pregnancy-related mortality ratios between 2011 and 2014 were as follows: 12.4 deaths per 100,000 live births for white women, 40.0 deaths per 100,000 live births for black women, and 17.8 deaths per 100,000 live births for women of other races ( 32 ); this inequity remains unchanged in the 2019 report of pregnancy-related deaths from 2015. ( 23 ) The 2018 report of 9 MMRCs revealed that greater proportions of pregnancy-related deaths of all pregnancy-associated deaths occurred among non-Hispanic black women compared with white women ( Fig 2 ). ( 22 )

Proportion of pregnancy-associated deaths determined to be pregnancy-related based on race and ethnicity. Adapted from Building U.S. Capacity to Review and Prevent Maternal Deaths. (2018). Report from 9 maternal mortality review committees. http://reviewtoaction.org/Report_from_Nine_MMRCs . ( 22 )

Black and Native American women also experience increased complications from pregnancy compared with white women, regardless of socioeconomic status and comorbidities. ( 47 ) Using 7 state inpatient databases from 2008 to 2010, Creanga et al identified race/ethnicity as an important predictor of maternal morbidity. ( 48 ) Although other factors were also identified as significant predictors of SMM, such as age less than 20 years or more than or equal to 35 years, self-pay or Medicaid coverage for delivery, low socioeconomic status, and presence of chronic medical conditions, they did not fully explain the observed racial/ethnic disparities in SMM. ( 48 ) Using the National Inpatient Sample from 2012 to 2015, Admon et al also found that SMM during delivery hospitalization was higher among all racial/ethnic groups compared with non-Hispanic whites. ( 49 ) The most common SMM was blood transfusion, which accounted for nearly 75% of all morbidity across racial/ethnic groups. The incidence of SMM was highest among women with multiple chronic conditions and particularly among those of color, suggesting increased case morbidity. ( 49 ) Grobman et al found that racial/ethnic disparities in maternal morbidity persisted even after controlling for patient-level factors and hospital of delivery. ( 50 ) In addition, racial/ethnic disparities in obstetric care delivery exist. Non-Hispanic blacks, Hispanics, and Asians all had lower odds of labor induction than non-Hispanic whites. The odds of receiving an episiotomy was increased in Asians but decreased in non-Hispanic blacks and Hispanics compared with non-Hispanic whites, ( 50 ) indicating that there may be biases in care delivery. Women of color also experience pregnancy-related complications that are associated with higher rates of death, such as tuberculosis, ( 51 ) or experience higher case fatality with conditions such as ectopic pregnancy. ( 52 )

The root cause of racial/ethnic inequities is the legacy of structural racism that permeates people’s lived experiences, including experiences in the health care system. One important driver of inequities in maternal health is distrust in the health system as a result of historical and contemporary discrimination, which often manifests as lower prenatal care utilization and adherence with treatment plans. An analysis of more than 2,000 responses to the Listening to Mothers III survey found that more than 40% of participants reported communication challenges in prenatal care and 24% perceived discrimination during birth hospitalization, predominantly among black or Hispanic women and uninsured women. ( 53 )

Another important driver of inequities is the variation in hospital quality of care during childbirth, in which women of color more commonly go to hospitals with higher risk-adjusted morbidity compared with the hospitals where white women go more commonly. ( 54 ) In an analysis of the black-white differences in hospital of delivery in New York City, Howell et al estimated that as much as 48% of the racial disparity in SMM could be attributed to differences in care quality at the hospital level. ( 55 ) A similar analysis among Hispanic women also showed that up to 37% of the ethnic disparity could be attributed to differences in care quality at the hospital level. ( 55 )

Solutions to reduce inequities span all levels, from policies to address racism and social determinants of health to improving quality of care delivery and experience of care during childbirth, to mobilizing community-based organizations to support women before, during, and after pregnancy. Some examples include standardizing and improving quality of care in hospitals, particularly among facilities that have higher risk-adjusted morbidity rates and also care for a disproportionate number of women of color. ( 56 ) In addition, developing disparity dashboards to track outcomes among specific groups is important for monitoring, evaluation, and quality improvement. ( 57 ) Training on implicit bias is critical across the health care workforce to sensitize individuals to the role implicit bias may play in their interactions with patients. Lastly, there are innovative antenatal and postnatal care delivery models that are being evaluated as strategies to close disparities, such as group antenatal care and postpartum home visits with integrated interdisciplinary health teams. ( 58 )

IMPROVING SAFETY AND QUALITY OF CHILDBIRTH CARE

With the increases in both maternal mortality and morbidity, there has been an increasing focus on quality of care at the hospital level in the days before and after childbirth. In addition to wide variation in SMM across hospitals, there is also substantial variation within hospitals. ( 56 ) The imperative to standardize and improve safety and quality is the foundation for reducing adverse maternal outcomes in the hospital setting. The most common mechanisms to achieve this end are 1) a focus on team communication and team training; 2) implementation of evidence-based safety bundles or toolkits to manage obstetric complications that are most likely to cause SMM and/or death; and 3) data-driven MMRCs that can provide specific recommendations for systems improvement to prevent future maternal deaths.

According to a review of sentinel events reported to the Joint Commission, failures in communication were the second leading root cause of SMM and maternal mortality and the leading root cause of perinatal deaths and injuries. ( 59 ) Key facilitators include leadership champions to build and support a culture of safety that encourages open communication among all team members and transparent, nonpunitive reporting of safety-critical events with a focus on systems improvement. ( 59 ) In addition, structured communication tools, such as safety huddles, safety checklists, “SBAR” (Situation, Background, Assessment, Recommendation) approach, and team training simulation such as TeamSTEPPS facilitate interprofessional communication and teamwork, particularly in acute situations that require coordination of resources and expertise. The maternal early warning triggers or criteria facilitate communication between bedside nurses and clinicians through increased clinical surveillance and responsiveness to patients with abnormal vital signs who may require prompt evaluation and treatment to prevent morbidity. ( 60 )( 61 )( 62 )

Safety bundles and/or toolkits that facilitate adherence with evidence-based guidelines have been critical efforts to reduce maternal morbidity and mortality in the United States. At a national level, multiple professional organizations and stakeholders came together to form the National Partnership for Maternal Safety, which developed safety bundles for obstetric hemorrhage, severe hypertension in pregnancy, and peripartum venous thromboembolism. ( 63 ) Since the introduction of universal pneumatic compression devices at the time of cesarean delivery and rapid treatment of severe hypertension, there was a reduction in maternal deaths from postcesarean pulmonary embolism and in deaths and morbidity related to hypertensive disorders. ( 64 )( 65 )( 66 )

The California Maternal Quality Care Collaborative (CMQCC) was developed as a public-private partnership and leveraged data from the Department of Public Health to support data-driven large-scale quality improvement initiatives to reduce maternal deaths and morbidity. ( 67 ) CMQCC-affiliated hospitals have demonstrated reductions in maternal morbidity from postpartum hemorrhage after implementing a comprehensive hemorrhage bundle compared with non–CMQCC-affiliated hospitals in California (20.8% vs 1.2%). ( 34 )

With federal funding from the Health Resources and Services Administration Maternal Child Health Bureau, the Alliance for Innovation on Maternal Health (AIM) was formed and led by partners from the ACOG Council on Patient Safety and Women’s Health Care and the National Partnership for Maternal Safety. ( 68 ) AIM is a state-based program that develops and provides implementation support for safety bundles. Each bundle has 4 components: readiness, recognition, response, and reporting and systems learning. ( 68 ) AIM operationalizes the bundle implementation and reporting systems through state-based teams, often organized as state perinatal quality collaboratives (PQCs). PQCs are defined as “state or multistate networks of multidisciplinary teams, working to improve measurable population outcomes for maternal and infant health by advancing evidence-informed clinical practices and processes using quality improvement principles.”( 69 ) The anchoring structure of PQCs relies on the department of public health, state hospital association, and clinician leadership. Additional members may include the state MMRC, community health organizations, patient advocacy groups, risk management, payers, and purchasers. ( 69 ) A critical function of the PQCs is to develop and sustain a robust data collection system for maternal health indicators at the state level.

Adjunct health system solutions to improve maternal outcomes include developing an obstetrics hospitalist workforce that may be best positioned to respond to uncommon emergencies ( 4 )( 70 ) and improve patient education at the time of discharge from the hospital. Although the obstetrics hospitalist workforce is growing across the United States, there remains wide variation regarding work models and scope of practice. ( 71 ) More data are needed to assess maternal outcomes in hospitals where a robust obstetrics hospitalist workforce manages intrapartum care. Similar to the integrated regional neonatal levels of care to improve perinatal mortality, maternal levels of care provide risk-appropriate care for those who would benefit from additional expertise and infrastructure because of preexisting comorbidities in pregnancy. ( 72 ) Implementation of regionalized maternal levels of care would allow for patients with high-risk conditions to be cared for at higher-volume hospitals with greater access to subspecialists. In addition, patient communication and education about danger signs, such as the POST-BIRTH tool, have been additional areas of focus to improve prompt recognition of symptoms and medical evaluation, especially once patients return home after childbirth. ( 73 )

The 2018 report of 9 MMRCs found that more than 60% of pregnancy-related deaths were preventable and the leading factors contributing to death were patient/family factors (namely, lack of knowledge about early warning signs to seek care), provider factors (misdiagnosis or ineffective treatments), and factors related to systems of care (lack of coordination between providers) ( Fig 3 ). ( 22 ) Most importantly, the MMRCs provided recommendations to prevent future maternal deaths, such as adopting levels of maternal care, ( 72 ) improving and enforcing policies and procedures on obstetric hemorrhage, and addressing health equity. Specifically, a California review of pregnancy-related cardiovascular deaths identified both patient and provider contributing factors, particularly a delay in patients seeking care as well as in provider response, which suggests an opportunity to improve patient education and standardize response protocols. ( 28 )

Preventability of pregnancy-related deaths by time of death in analysis of 9 state maternalmortality review committees. Adapted from Building U.S. Capacity to Review and Prevent Maternal Deaths. (2018). Report from 9 maternalmortality review committees. http://reviewtoaction.org/Report_from_Nine_MMRCs . ( 22 )

CURRENT HEALTH CARE POLICY TO ADDRESS MATERNAL MORTALITY

On December 21, 2018, the Preventing Maternal Deaths Act (HR 1318) was signed into law. This legislation allocates federal funding to support states in establishing and sustaining MMRCs. ( 74 ) One challenge will be standardizing data collection and reporting systems among the various MMRCs.

Other maternal health bills in Congress at this time are the Maternal Care Access and Reducing Emergencies (CARE) Act, the Rural Maternal and Obstetric Modernization of Services (MOMS) Act, and the Mothers and Offspring Mortality and Morbidity Awareness (MOMMA) Act. The CARE Act, introduced by California Senator Kamala Harris, focuses on dismantling structural racism through training programs around implicit bias for clinicians. The MOMS Act, introduced by North Dakota Senator Heidi Heitkamp, addresses the disparities in access to obstetric care for women in rural communities by creating regional networks and increasing workforce capacity in rural areas. The MOMMA Act, introduced by Illinois Representative Robin Kelly, seeks to expand Medicaid through 1 year after delivery, standardize data collection through the CDC, establish and enforce national emergency obstetric protocols, and improve culturally competent care. In addition, there are multiple bills at the state and federal levels around expanding Medicaid through 1 year after delivery and providing Medicaid reimbursement for doula services.

PREPREGNANCY AND INTERPREGNANCY HEALTH

Pregnancy conditions, such as hypertensive disease and gestational diabetes, are known risk factors for cardiovascular disease later in life and increased early mortality. ( 42 )( 75 ) Other adverse pregnancy outcomes such as preterm labor and fetal growth restriction may also be associated with increased lifelong cardiovascular risk. ( 76 ) The postpartum period is a time of significant biological, psychological, and social transition with increased risk of complications, yet 10% to 40% of women do not attend any postpartum visit between 4 and 12 weeks. ( 77 ) During pregnancy and postpartum care, obstetricians have an opportunity to provide anticipatory guidance; arrange for appropriate follow-up for chronic health conditions, mental health, and substance use disorders; and identify and educate patients about early warning signs of SMM. According to the most recent CDC report, the majority of unintentional deaths occurred between 6 weeks and 1 year after delivery, highlighting the importance of the continuum of care that extends beyond the traditional 6-week postpartum period. ( 23 ) ACOG has revised recommendations for postpartum care to become an ongoing process of addressing recovery from birth, newborn care, psychosocial and sexual well-being, contraception, chronic disease management, health maintenance, and a transition to ongoing well-woman care, rather than a single encounter. ( 78 ) The prepregnancy and interpregnancy periods are windows of opportunity for implementing risk-reducing interventions for women with multiple medical conditions, mental health issues, or substance use disorders to optimize outcomes for future pregnancies and long-term well-being. Improving health systems to allow longitudinal continuous care from pregnancy and beyond is critical to reduce maternal mortality. ( 79 )

Pregnancy-related deaths have been steadily rising in the United States and are not just a result of improved data acquisition. Cardiovascular conditions, obstetric hemorrhage, and self-harm or unintentional harm are important causes of pregnancy-related deaths; significant inequities exist between non-Hispanic black and non-Hispanic white women. The majority of pregnancy-related deaths are preventable. Implementation of safety bundles, team training, integrated multidisciplinary care for high-risk patients, risk-stratified levels of maternal care, improvements in communication between providers and patients regarding early warning signs, and addressing structural racism and the social determinants of health are all strategies for improving maternal safety, quality and equity. Health care policy to improve funding and resources for standardized, state-based review of pregnancy-related deaths are important steps to reverse rising rates and close persistent inequities in maternal morbidity and mortality.

Practice Gaps

• In contrast to other high-income countries, the maternal death rate in the United States has been rising for over 20 years with persistent racial/ethnic inequities.
• Initiatives to improve safety, quality, and equity of care during pregnancy, delivery, and beyond are essential to optimize maternal health outcomes.

Objectives After completing this article, readers should be able to:

• Explain the definitions of pregnancy-related and pregnancy-associated deaths and the data challenges in the United States.
• Recognize key contributors to rising maternal deaths and persistent inequities in the United States.
• Identify key strategies and solutions for improving maternal health.

American Board of Pediatrics Neonatal-Perinatal Content Specifications

• Know the effects on the fetus and/or newborn infant of maternal cardiac disease and its management.
• Know the essentials of prenatal care, including risk assessment, perinatal referral, screening, and standard monitoring.
• Know how maternal obesity may influence pregnancy and pregnancy outcome.
• Know the components of pre- and periconceptional health care (including nutritional requirements during pregnancy) that influence pregnancy outcomes.
• Know the issues in the organization of perinatal care (e.g., regionalization, transport, practice guidelines, benchmarking data, quality improvement).

Acknowledgments

AUTHOR DISCLOSURE Dr Collier is supported by the Reproductive Scientist Development Program (K12HD000849), the Eunice Kennedy Shriver National Institute of Child Health & Human Development, and Burroughs Wellcome Fund as part of the Reproductive Scientist Development Program. Dr Molina has disclosed no financial relationships relevant to this article. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.

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Maternal Mortality Rates in the United States, 2021

Data source and methods, suggested citation.

by Donna L. Hoyert, Ph.D., Division of Vital Statistics

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This report presents maternal mortality rates for 2021 based on data from the National Vital Statistics System. A maternal death is defined by the World Health Organization as “the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and the site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes” ( 1 ). Maternal mortality rates, which are the number of maternal deaths per 100,000 live births, are shown in this report by age group and race and Hispanic origin.

This report updates a previous one that showed maternal mortality rates for 2018–2020 ( 2 ). In 2021, 1,205 women died of maternal causes in the United States compared with 861 in 2020 and 754 in 2019 ( 2 ). The maternal mortality rate for 2021 was 32.9 deaths per 100,000 live births, compared with a rate of 23.8 in 2020 and 20.1 in 2019 ( Table ).

In 2021, the maternal mortality rate for non-Hispanic Black (subsequently, Black) women was 69.9 deaths per 100,000 live births, 2.6 times the rate for non-Hispanic White (subsequently, White) women (26.6) ( Figure 1 and Table ). Rates for Black women were significantly higher than rates for White and Hispanic women. The increases from 2020 to 2021 for all race and Hispanic-origin groups were significant.

Rates increased with maternal age. Rates in 2021 were 20.4 deaths per 100,000 live births for women under age 25, 31.3 for those aged 25–39, and 138.5 for those aged 40 and over ( Figure 2 and Table ). The rate for women aged 40 and over was 6.8 times higher than the rate for women under age 25. Differences in the rates between age groups were statistically significant. The increases in the rates between 2020 and 2021 for each of these age groups were statistically significant.

Data are from the National Vital Statistics System mortality file ( 3 ). Consistent with previous reports, the number of maternal deaths does not include all deaths occurring to pregnant or recently pregnant women, but only deaths with the underlying cause of death assigned to International Statistical Classification of Diseases, 10th Revision code numbers A34, O00–O95, and O98–O99. Maternal mortality rates are per 100,000 live births, based on data from the National Vital Statistics System natality file. Maternal mortality rates fluctuate from year to year because of the relatively small number of these events and possibly due to issues with the reporting of maternal deaths on death certificates ( 4 ) . Efforts to improve data quality are ongoing, and these data will continue to be evaluated for possible errors. Data are shown for only the three largest race and Hispanic-origin groups for which statistically reliable rates can be calculated.

• World Health Organization. International statistical classification of diseases and related health problems, 10th revision (ICD–10). 2008 ed. Geneva, Switzerland. 2009.
• Hoyert DL. Maternal mortality rates in the United States, 2020. NCHS Health E-Stats. 2022. DOI: https://doi.org/10.15620/cdc:113967 .
• Xu JQ, Murphy SL, Kochanek KD, Arias E. Mortality in the United States, 2021. NCHS Data Brief, no 456. Hyattsville, MD: National Center for Health Statistics. 2022. DOI: https://dx.doi.org/10.15620/cdc:122516 .
• Hoyert DL, Miniño AM. Maternal mortality in the United States: Changes in coding, publication, and data release, 2018. National Vital Statistics Reports; vol 69 no 2. Hyattsville, MD: National Center for Health Statistics. 2020.

Hoyert DL. Maternal mortality rates in the United States, 2021. NCHS Health E-Stats. 2023. DOI: https://dx.doi.org/10.15620/cdc:124678 .

Table. Number of live births, maternal deaths, and maternal mortality rates, by race and Hispanic origin and age: United States, 2018–2021

* Rate does not meet National Center for Health Statistics standards of reliability. 1 Maternal mortality rates are deaths per 100,000 live births. 2 Includes deaths for race and Hispanic-origin groups not shown separately, including women of multiple races and origin not stated. 3 Race groups are single race.

NOTES: Maternal causes are those assigned to code numbers A34, O00–O95, and O98–O99 of the International Classification of Diseases, 10th Revision . Maternal deaths occur while pregnant or within 42 days of being pregnant.

SOURCE: National Center for Health Statistics, National Vital Statistics System, Natality and Mortality.

Figure 1. Maternal mortality rates, by race and Hispanic origin: United States, 2018–2021

Figure 2. Maternal mortality rates, by age group: United States, 2018–2021

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Maternal mortality

• Every day in 2020, almost 800 women died from preventable causes related to pregnancy and childbirth.
• A maternal death occurred almost every two minutes in 2020.
• Between 2000 and 2020, the maternal mortality ratio (MMR, number of maternal deaths per 100 000 live births) dropped by about 34% worldwide.
• Almost 95% of all maternal deaths occurred in low and lower middle-income countries in 2020.
• Care by skilled health professionals before, during and after childbirth can save the lives of women and newborns.

Maternal mortality is unacceptably high. About 287 000 women died during and following pregnancy and childbirth in 2020.  Almost 95% of all maternal deaths  occurred in low and lower middle-income countries in 2020, and most could have been prevented .

Sustainable Development Goal (SDG)  regions and sub-regions  are used here. Sub-Saharan Africa and Southern Asia accounted for around 87% (253 000) of the estimated global maternal deaths in 2020. Sub-Saharan Africa alone accounted for around 70% of maternal deaths (202 000), while Southern Asia accounted for around 16% (47 000).

At the same time, between 2000 and 2020, Eastern Europe and Southern Asia achieved the greatest overall reduction in maternal mortality ratio (MMR): a decline of 70% (from an MMR of 38 to 11) and 67% (from an MMR of 408 down to 134), respectively. Despite its very high MMR in 2020, sub-Saharan Africa also achieved a substantial reduction in MMR of 33% between 2000 and 2020. Four SDG sub-regions roughly halved their MMRs during this period: Eastern Africa, Central Asia, Eastern Asia, and Northern Africa and Western Europe reduced their MMR by around one third. Overall, the MMR in least-developed countries* declined by just under 50%. In land locked developing countries the MMR decreased by 50% (from 729 to 368). In small island developing countries the MMR declined by 19% (from 254 to 206).

Where do maternal deaths occur?

The high number of maternal deaths in some areas of the world reflects inequalities in access to quality health services and highlights the gap between rich and poor. The MMR in low-income countries in 2020 was 430 per 100 000 live births versus 13 per 100 000 live births in high income countries.

Humanitarian, conflict, and post-conflict settings hinder progress in reducing the burden of maternal mortality. In 2020, according to the Fragile States Index  (1) , 9 countries were “very high alert” or “high alert” (from highest to lowest: Yemen, Somalia, South Sudan, the Syrian Arab Republic, the Democratic Republic of the Congo, the Central African Republic, Chad, Sudan and Afghanistan); these countries had MMRs ranging from 30 (the Syrian Arab Republic) to 1223 (South Sudan) in 2020. The average MMR for very high and high alert fragile states in 2020 was 551 per 100 000, over double the world average.

Women in low-income countries have a higher lifetime risk of death of maternal death. A woman’s lifetime risk of maternal death is the probability that a 15-year-old woman will eventually die from a maternal cause. In high income countries, this is 1 in 5300, versus 1 in 49 in low-income countries.

Why do women die?

Women die as a result of complications during and following pregnancy and childbirth. Most of these complications develop during pregnancy and most are preventable or treatable. Other complications may exist before pregnancy but are worsened during pregnancy, especially if not managed as part of the woman’s care. The major complications that account for nearly 75% of all maternal deaths are  (2) :

• severe bleeding (mostly bleeding after childbirth);
• infections (usually after childbirth);
• high blood pressure during pregnancy (pre-eclampsia and eclampsia);
• complications from delivery; and
• unsafe abortion.

How can women’s lives be saved?

To avoid maternal deaths, it is vital to prevent unintended pregnancies. All women, including adolescents, need access to contraception, safe abortion services to the full extent of the law, and quality post-abortion care.

Most maternal deaths are preventable, as the health-care solutions to prevent or manage complications are well known. All women need access to high quality care in pregnancy, and during and after childbirth. Maternal health and newborn health are closely linked. It is particularly important that all births are attended by skilled health professionals, as timely management and treatment can make the difference between life and death for the women as well as for the newborns. 

Severe bleeding  after birth can kill a healthy woman within hours if she is unattended. Injecting oxytocics immediately after childbirth effectively reduces the risk of bleeding.

Infection  after childbirth can be eliminated if good hygiene is practiced and if early signs of infection are recognized and treated in a timely manner.

Pre-eclampsia  should be detected and appropriately managed before the onset of convulsions (eclampsia) and other life-threatening complications. Administering drugs such as magnesium sulfate for pre-eclampsia can lower a woman’s risk of developing eclampsia.

Why do women not get the care they need?

Poor women in remote areas are the least likely to receive adequate health care  (3).  This is especially true for SDG regions with relatively low numbers of skilled health care providers, such as Sub-Saharan Africa and Southern Asia.

The latest available data suggest that in most high income and upper middle income countries, approximately 99% of all births benefit from the presence of a trained midwife, doctor or nurse. However, only 68% in low income and 78% in lower-middle-income countries are assisted by such skilled health personnel  (4).

Factors that prevent women from receiving or seeking care during pregnancy and childbirth are:

• health system failures that translate to (i) poor quality of care, including disrespect, mistreatment and abuse, (ii); insufficient numbers of and inadequately trained health workers, (iii); shortages of essential medical supplies; and (iv) the poor accountability of health systems;.
• social determinants, including income, access to education, race and ethnicity, that put some sub-populations at greater risk;
• harmful gender norms and/or inequalities that result in a low prioritization of the rights of women and girls, including their right to safe, quality and affordable sexual and reproductive health services; and
• external factors contributing to instability and health system fragility, such as climate and humanitarian crises.

To improve maternal health, barriers that limit access to quality maternal health services must be identified and addressed at both health system and societal levels.

What was the impact of COVID-19 pandemic on maternal mortality?

It is clear from the data that the stagnation in maternal mortality reductions pre-dates the start of the COVID-19 pandemic in 2020. The COVID-19 pandemic may have contributed to the lack of progress but does not represent the full explanation.

The level of maternal mortality during the COVID-19 pandemic may have been impacted by two mechanisms: deaths where the woman died due to the interaction between her pregnant state and COVID-19 (known as an indirect obstetric deaths), or deaths where pregnancy complications were not prevented or managed due to disruption of health services.

A robust global assessment of the impact of COVID-19 on maternal mortality is not possible from the data currently available: only around 20% of the countries and territories have thus far reported empirical data on their maternal mortality levels in 2020, and high-income and/or relatively smaller populations are over-represented in this group – with implications for generalizability of findings.

The current estimates only extend to include the year 2020. Given the limited data, we expect these estimates to be revised in future updates.

The Sustainable Development Goals and maternal mortality

In the context of the Sustainable Development Goals (SDG), countries have united behind the target to accelerate the decline of maternal mortality by 2030. SDG 3 includes an ambitious target: “reducing the global MMR to less than 70 per 100 000 births, with no country having a maternal mortality rate of more than twice the global average”.

The global MMR in 2020 was 223 per 100 000 live births; achieving a global MMR below 70 by the year 2030 will require an annual rate of reduction of 11.6%, a rate that has rarely been achieved at the national level. However, scientific and medical knowledge are available to prevent most maternal deaths. With 10 years of SDGs remaining, now is the time to intensify coordinated efforts, and to mobilize and reinvigorate global, regional, national, and community-level commitments to end preventable maternal mortality.

WHO response

Improving maternal health is one of WHO’s key priorities. WHO works to contribute to the reduction of maternal mortality by increasing research evidence, providing evidence-based clinical and programmatic guidance, setting global standards, and providing technical support to Member States on developing and implementing effective policy and programmes.

As defined in the  Strategies toward ending preventable maternal mortality (EPMM)  and  Ending preventable maternal mortality: a renewed focus for improving maternal and newborn health and well-being , WHO is working with partners in supporting countries towards:

• addressing inequalities in access to and quality of reproductive, maternal and newborn health care services;
• ensuring universal health coverage for comprehensive reproductive, maternal and newborn health care;
• addressing all causes of maternal mortality, reproductive and maternal morbidities, and related disabilities;
• strengthening health systems to collect high quality data in order to respond to the needs and priorities of women and girls; and
• ensuring accountability in order to improve quality of care and equity.

* For details of countries considered in the group of “least developed” please refer to standard country or area codes for statistical use (M49).

1. Fragile States Index. Available at: https://fragilestatesindex.org/data/.

2. Say L, Chou D, Gemmill A et al.  Global Causes of Maternal Death: A WHO Systematic Analysis.  Lancet Global Health. 2014;2(6): e323-e333.

3. Samuel O, Zewotir T, North D. Decomposing the urban–rural inequalities in the utilisation of maternal health care services: evidence from 27 selected countries in sub-Saharan Africa. Reprod Health 18, 216 (2021).

4. World Health Organization and United Nations Children’s Fund. WHO/UNICEF joint database on SDG 3.1.2 Skilled Attendance at Birth.  Available at :  https://unstats.un.org/sdgs/indicators/database/ .

• Maternal mortality: Levels and trends 2000–2020
• Global Health Observatory: Maternal mortality
• Global causes of maternal death: a WHO systematic analysis . The Lancet Global Health, 6 May 2014
• WHO's work on maternal health
• Every Woman Every Child‘s Global Strategy for Women’s, Children’s and Adolescents’ Health
• Ending preventable maternal mortality (EPMM)