A groundbreaking new study from researchers at Boston University School of Public Health reveals profound connections between maternal mortality and infant health outcomes in the United States, a subject that, until now, has received scant attention despite its critical importance. Analyzing over two decades of data from Massachusetts, the investigation offers the first extensive longitudinal insight into how a mother’s death during or shortly after pregnancy dramatically increases the risk of infant mortality and severe infant health complications.
The research taps into a robust dataset spanning from 1999 through 2021, encompassing more than 1.6 million live births in Massachusetts. This longitudinal, population-based approach allowed the team to correlate maternal deaths—including those occurring anytime during pregnancy and up to one year postpartum—with corresponding infant mortality rates and hospitalization incidents. The findings illuminate an alarming disparity: infants whose mothers suffered pregnancy-associated deaths exhibit mortality rates nearly fourteen times higher than infants whose mothers survived pregnancy and postpartum periods.
Even more striking is the revelation that infant mortality soars to an astounding 22-fold increase when maternal death stems from severe maternal morbidity (SMM) conditions such as renal failure, hypertensive disorders including eclampsia, and sepsis. This severe maternal morbidity manifests as life-threatening illnesses or complications during or shortly after pregnancy, further endangering infant survival prospects. The intertwining nature of maternal and infant health outcomes demonstrated by this study underscores the inseparable biological and social links between mother and child.
Beyond mortality statistics, the study extends its scope to survivors—those infants who outlive their mothers’ pregnancy-associated deaths yet remain vulnerable. Non-premature infants of these mothers showed a 35 percent higher chance of hospitalization during their first year of life. Even maternal experience of SMM, without death, increased infant hospitalizations by 10 percent. These statistics spotlight a continuum of adverse health consequences for infants whose mothers experience life-threatening pregnancy-related health crises, whether fatal or nonfatal.
The implications of this study are particularly crucial amidst contemporary policy debates and restructuring of maternal mortality review boards across various states, some of which have reduced or entirely eliminated oversight mechanisms dedicated to investigating maternal deaths. The researchers emphasize that these findings should catalyze renewed investment in maternal health infrastructure, prevention strategies, and postnatal care systems, stepping away from dismantling essential surveillance and support.
Dr. Eugene Declercq, leading the investigation, stresses the critical nature of recognizing the holistic relationship between maternal and infant health outcomes. He articulates that improving health outcomes for women is not only inherently valuable but also foundational for safeguarding infant health and nurturing family well-being over the long term. This dual health imperative demands integrated, family-centered public health interventions and policies.
Methodologically, the study represents a multidisciplinary collaboration involving Boston University, Tufts University School of Medicine, the Massachusetts Department of Public Health, the University of Colorado, and Evalogic Services, Inc. The team meticulously utilized hospital records linked longitudinally to capture the complex interplay of maternal deaths and infant health outcomes in a comprehensive manner seldom achieved in U.S. research.
Among the risk factors identified, maternal age over 40, public insurance status, opioid use, and non-Hispanic Black ethnicity correlated with adverse infant outcomes, although these were outstripped in impact by maternal death or severe morbidity status. This suggests that while socioeconomic and demographic factors play significant roles in infant health, the biological and direct health consequences of maternal mortality and morbidity wield an exceptionally potent influence.
The study reported an overall pregnancy-associated mortality ratio in Massachusetts at 29.3 per 100,000 live births and an infant mortality rate of 4.06 per 1,000 live births. Where the mother died, infant mortality surged to 55 per 1,000, and alarmingly to 87.9 per 1,000 when linked to severe maternal morbidity conditions. Causes of infant death varied by gestational age, with premature infants succumbing predominantly to hypoxic ischemic encephalopathy and congenital heart anomalies, while full-term infants died from injuries, birth asphyxia, congenital malformations, and unexplained reasons.
It is important to note Massachusetts holds the distinction of having the lowest infant mortality rate nationally, making these outcomes arguably conservative estimates of the impact maternal mortality and morbidity may have in other U.S. states with higher baseline infant mortality. The potential public health fallout across the country, particularly in areas with less robust maternal and child health resources, could be even more alarming.
Coauthor Dr. Howard Cabral highlights how linked longitudinal data, such as that housed in Massachusetts’s Pregnancy-to-Early Life database, exposes critical missed opportunities for health system interventions targeting mothers and infants at risk. The data reinforces calls for more proactive surveillance and follow-up to mitigate adverse health trajectories resulting from maternal mortality and severe morbidity events.
This study breaks new ground by quantifying the deeply interwoven biological and social consequences of maternal death and morbidity on infant survival and health —an area which public health policies and programs urgently need to address. It compels a reassessment of maternal healthcare priorities not in isolation but as an essential component underpinning infant health and well-being.
Boston University’s pioneering work provides compelling evidence that maternal health is inextricably linked to the earliest determinants of infant health outcomes. These revelations demand attention not just from medical professionals but also from policymakers, public health officials, and society at large as the U.S. continues to grapple with stubbornly high maternal mortality rates relative to peer nations.
Without sustained support and investment in maternal care, this spiraling impact threatens to widen health disparities and undermine progress in infant survival and health. The study hence acts as a clarion call: to protect infant health, we must fundamentally improve and support maternal health through comprehensive, continuous, and equitable healthcare interventions that begin before conception and continue through the postpartum period and beyond.
Subject of Research: People
Article Title: Relationship Between Maternal Death and Infant Outcomes in a Longitudinal, Population-Based Dataset
News Publication Date: September 26, 2025
Web References:
– https://journals.lww.com/greenjournal/abstract/9900/relationship_between_maternal_death_and_infant.1371.aspx
– http://dx.doi.org/10.1097/AOG.0000000000006071
References: Boston University School of Public Health et al., published in Obstetrics & Gynecology, September 2025.
Keywords: Mothers, Childbirth, Obstetrics, Prenatal care, Postnatal care, Pregnancy complications, Public health, Human health, Children, Infants, Pregnancy
