Beyond Maternal Mortality: How Severe Morbidity Reveals Policy Gaps in Maternal Care

More people die during and after childbirth in the United States than in any other high-income country — but that is not the whole picture. Every year, thousands of people experience serious health complications from pregnancy and childbirth that have profound consequences for them and their babies. These incidents, defined by the U.S. Centers for Disease Control and Prevention (CDC) as severe maternal morbidity (SMM), are far more common than maternal deaths, and strategies that prevent them could save women and their families from significant suffering while also offering a window into how to prevent maternal deaths.

The concept of severe maternal morbidity grew out of a desire to paint a broader picture of maternal health and well-being. Initially established by the CDC in 2012, SMM, or “unexpected outcomes of labor and delivery that can result in significant short- or long-term health consequences,” is a strong indicator of poor health outcomes for mothers and infants in the year after childbirth. A large Massachusetts study from 2025 found that infants were almost four times more likely to die at birth or in the first year of life when their mother experienced SMM (15.7 per 1,000 live births vs 4.0 per 1,000). Women experiencing SMM were a staggering 31 times more likely to die than their peers without SMM (745 per 100,000 vs 24 per 100,000). In addition to increasing maternal and infant mortality risks, SMM has significant short- and long-term social, psychological, physical, and financial consequences for women, infants, and their families.

SMM, being more common than maternal mortality, offers a broader examination of births than what is available from studying the rarer occurrences of maternal deaths. There were 817 pregnancy-related deaths (22.3 deaths per 100,000 live births) in 2022 and an estimated 32,505 people impacted by severe maternal morbidity during their birth hospitalization. The CDC recently released statistics for 2024: there were 649 maternal deaths that year (17.9 deaths per 100,000 live births). Given the relationship between SMM and maternal mortality, SMM rates also may have declined since 2022, but more recent SMM data are needed to definitively assess trends, as the two measures do not move in lockstep (see “How We Conducted This Study” for more on how we measure and define SMM).

This brief provides updated estimates of SMM overall and across demographic and geographic characteristics, including race, insurance type, and state of residence. We also highlight the relationship between SMM and maternal mortality, as well as differences in delivery costs between mothers with and without SMM.

Key Findings

Both severe maternal morbidity and pregnancy-related mortality rates remained remarkably steady between 2010 and 2019, followed by rapid increases in 2020 and 2021 during the COVID-19 pandemic, and a nearly 8 percent decrease between 2021 and 2022. From 2022 to 2023, the pregnancy-related mortality rate had a 6 percent decrease. These data reaffirm the relationship between SMM and maternal deaths in the U.S.

There is wide variation in SMM rates across states. States with the highest rates of SMM, including New York, the District of Columbia, Massachusetts, and California, have up to double the rates of the lowest reporting states of Wyoming, Nebraska, and South Dakota.

Unexpectedly, states with the highest SMM rates have some of the best overall health outcomes in the country — with Massachusetts, the District of Columbia, and New York among the top six states in the Commonwealth Fund’s latest health system performance rankings — while South Dakota and Wyoming both rank in the bottom half. SMM in states also has an inverse relationship with state pregnancy-related mortality and infant mortality rates (data not shown).

This most likely reflects differences in state reporting of the conditions that make up the SMM algorithm, meaning overall SMM rates may not be truly comparable at the state level. Alternatively, higher SMM rates in states that report low maternal mortality could reflect their success in preventing maternal deaths in high-risk conditions.

SMM itself overall and its specific components occur rarely. The overall SMM rate in Massachusetts for 2019 through mid-2024 was 108.4 per 10,000, or about 1.1 percent, one of the higher rates in the U.S. (see the previous exhibit for states with the highest and lowest SMM rates). Six conditions occurred in at least 1 in 1,000 births. The most common condition was acute renal failure (when kidneys suddenly cannot filter waste products from the blood) at 40.4 per 10,000. For nine of the 20 components, the frequency was less than 1.2 per 10,000, and hence they have only a marginal impact on the overall rate, at least in Massachusetts.

The national data available on SMM are reported by three specific racial and ethnic groups only — Hispanic, non-Hispanic Black, and non-Hispanic white — and a fourth group combining all other non-Hispanic populations, including Asian American, Native Hawaiian, and Pacific Islanders and American Indian and Alaska Natives. Non-Hispanic Black people have an SMM rate that is consistently about 90 percent higher than non-Hispanic white people, with this gap widest during the COVID-19 pandemic. Hispanic women and the non-Hispanic “other” group had similar SMM rates and trends, averaging 25 percent to 35 percent higher than non-Hispanic whites. This contrasts with pregnancy-related mortality rates, where Hispanic and non-Hispanic Asian women die at lower rates than their non-Hispanic white counterparts. The “other” group was more affected by SMM than other racial and ethnic groups during the pandemic, perhaps because American Indian and Alaska Native mothers died at a rate four times higher than non-Hispanic white mothers during this period.

Unlike data on race and ethnicity, which only became available in 2016, SMM data by age date back to 2010. There was very little difference in SMM rates among mothers between ages 12 and 34, and each age group experienced a comparable surge during the pandemic. For women giving birth at 35 or older, SMM rates were consistently about 70 percent higher than for women under age 35. Age-related differences are even more stark in pregnancy-related mortality rates. In 2024, women age 35 and older died of pregnancy-related causes at more than double the rate of those under 35 — 30.8 per 100,000 live births compared to 14.6. Research suggests that higher rates of pregnancy-related mortality among those 35 and older is driven by higher prevalence of conditions such as obstetric hemorrhage, postpartum cardiomyopathy, obstetric embolism, and eclampsia and preeclampsia relative to women under 35.

Severe maternal morbidity is associated with indicators of poverty. There is a 28 percent difference in SMM rates between women with public insurance like Medicaid and those with private insurance. Similarly, women in the lowest income group experience SMM more than women in any other income groups.

SMM is recorded at higher rates in large metropolitan areas compared to medium or small communities and rural areas. This could be interpreted as referral systems working well, meaning women experiencing higher-risk pregnancies are referred effectively to better-equipped hospitals. This is the goal of the CDC’s LOCATe campaign, which helps states create standardized assessments to ensure that pregnant women and infants get the right care in the right place at the right time.

SMM is more than twice as likely to be recorded in a metropolitan teaching hospital than in a rural hospital, and much more likely in a hospital with more than 1,000 deliveries than one with fewer than 500. Whether this is the result of an effective referral system funneling higher-risk cases to appropriate facilities or better reporting of SMM-related conditions at larger facilities cannot be determined from these data, but trying to concentrate higher-risk births in facilities that offer a higher level of care (like larger teaching hospitals) has been a goal of recent efforts, such as the Levels of Maternal Care consensus document.

The rate of SMM is 34 percent greater in safety-net hospitals than non-safety-net hospitals. It is also more common in publicly owned hospitals than privately owned ones, which includes both nonprofit and for-profit hospitals. Both safety-net and publicly owned hospitals serve larger proportions of patients with Medicaid and without insurance — characteristics associated with SMM.

One particularly high-risk group for severe maternal morbidity is women who have experienced it in a previous delivery. In a population-based study, the rate of SMM among women who did not experience it previously was 61 per 10,000, or slightly less than 0.6 percent. Among women with a prior experience of SMM, the rate rises to 704 per 10,000, or slightly over 7 percent.

There are wide disparities across race and ethnicity: the likelihood of a non-Hispanic white mother experiencing SMM rose from 46 per 10,000 when she hadn’t had a prior case of SMM to 525 with a prior case. For non-Hispanic Black mothers, the SMM rate increased from 103 to 1,245 per 10,000, meaning one in eight non-Hispanic Black women with SMM in a prior birth are at high risk for SMM in a subsequent birth. The same study found women with SMM in their first pregnancy were significantly more likely to be hospitalized between pregnancies than women without prior SMM (data not shown). These findings indicate the need to carefully monitor women who experience SMM during any subsequent pregnancies.

Between 2014 and 2019, births involving SMM were more than twice the cost of those births without SMM. The difference is consistent across racial and ethnic groups, but for all births to non-Hispanic Asian Pacific Islander mothers, the cost of births involving SMM rose to more than $13,600.

Discussion

Severe maternal morbidity undermines maternal health and well-being in the United States. In addition to the up to 40,000 people a year who are impacted, SMM increases the odds of maternal death by 31 times and infant death by almost four times. These are not isolated clinical events but rather clear signals of people not getting the care that they need due to breakdowns in transitions of care, prevention, timely referral, chronic disease management, and postpartum continuity of care.

Cases of SMM are unevenly distributed, with women over age 35, non-Hispanic Black mothers, those relying on public insurance, and those in the lowest income quartile at greatest risk. Effectively tackling the problem of SMM necessitates addressing these disparities. Key steps toward lowering SMM rates in the U.S. include the following:

Modernizing and safeguarding maternal health data systems. Accurate measurement of severe maternal morbidity is foundational to prevention, but there are considerable challenges in doing so. The SMM algorithm applied to hospital discharge data excludes many prenatal and postpartum health and mental health conditions. While the measure has great value since it includes data on all birth hospitalizations, it misses serious morbidity that occurs outside of childbirth, undercounting conditions such as postpartum depression and anxiety, despite their well-documented impacts on maternal well-being and mortality risk.

Alongside a standard definition of SMM to improve comparability, a more comprehensive measure of SMM that includes pregnancy, one year postpartum, and mental and behavioral health indicators would improve our understanding of SMM.

Maternal Mortality Review Committees and the Pregnancy Risk Assessment Monitoring System (PRAMS) are also critical resources for understanding and tracking maternal health, but the latter is under threat due to federal funding cuts. Sustaining and improving data collection through appropriate resource allocation, including funding and expertise, is critically important.

Ensuring insurance coverage throughout pregnancy and one year postpartum. Although severe maternal morbidity is relatively rare — impacting approximately 32,505 women out of 3.6 million pregnancies each year — its consequences are profound, and many cases are preventable. Prevention is possible through robust health coverage that guarantees timely access to affordable, high-quality care. Coverage disruptions during pregnancy and postpartum impact early identification and management of serious complications. While coverage is a key part of the solution, it is the “floor” that supports additional, critical health system solutions.

Over 40 percent of births are paid for by Medicaid. Since SMM is more common among people with public insurance and low income, substantial Medicaid cuts in the July 2025 budget reconciliation bill, H.R. 1, will likely undermine health coverage and may increase SMM rates. Implementing 12-month postpartum coverage, which most states have now adopted, is key to preventing health access gaps after birth. Additionally, Medicaid managed care has an opportunity to ensure contracts provide standard postpartum care coverage.

These steps should also include improving patient transitions from obstetrics to primary care and supporting community birthing models of care. This can be done by aligning payment models to support postpartum standards, team-based perinatal care, midwifery care, doulas, and behavioral health providers. While comprehensive community-based care exists, its survival is under threat, with nearly two dozen birthing centers closing since 2023 due in part to financial pressures, including payments from insurers not covering the full cost of services.

Strengthening regional care systems and referral networks. The surprising finding that states with lower maternal mortality rates tend to have higher incidence of SMM, and vice versa, merits further investigation. Whether this reflects flaws and inconsistencies in the way SMM is measured across states, or states successfully preventing maternal deaths in high-risk cases, impacts our strategies for addressing SMM.

SMM is more frequently recorded in metropolitan teaching hospitals and safety-net facilities. This could be because rural and non-teaching facilities are effectively identifying high-risk patients and referring them to higher-capacity facilities, which are a critical element of SMM prevention. Prevention depends on ensuring that high-risk pregnancies are identified early and managed in facilities equipped to respond.

Efforts are underway to improve maternal health care, particularly in high-risk cases, through the continued growth of Perinatal Quality Collaboratives, which are state or multistate networks of teams focusing on improving care quality for mothers and infants. These collaboratives have prioritized reducing severe maternal morbidity, especially pregnancy complications associated with high blood pressure and hemorrhage. Additionally, there are campaigns to better identify higher-risk patients earlier in pregnancy and develop communication systems and transfer protocols to ensure they receive care at an appropriate facility.

In the future, there may be opportunities to leverage rural health funding, such as the Rural Health Transformation Program, to bolster access to maternal health services in underserved communities. Investing in telehealth and collaborative e-learning models can also create opportunities to further strengthen rural capacity and regionalization of care.

Conclusion

Addressing today’s severe maternal morbidity is essential to preventing tomorrow’s maternal and infant mortality. Doing so also improves people’s quality of life, lowers risks for future pregnancies, and reduces health care costs overall. SMM is both a critical warning sign and an opportunity — by signaling preventable harm within the health system, it offers a measurable target for quality and safety improvements.

To improve SMM rates, the health system must be designed to support people before, during, and after pregnancy with well-resourced and coordinated care facilities that are accountable for providing safe, equitable, high-quality care.