A large-scale study led by Harvard T.H. Chan School of Public HealthandMass General Brigham reveals that stillbirths affect more pregnancies than earlier estimates suggested, with rates exceeding the longstanding national average. Researchers reviewed over 2.7 million pregnancies from 2016 to 2022, finding more than one in 150 deliveries ended in stillbirth—considerably higher than the CDC’s figure of one in 175.
Significant Share of Stillbirths Occur With No Identified Clinical Risks
While most stillbirths had identifiable risk factors, such as obesity, hypertension, or diabetes, a substantial portion occurred in otherwise healthy pregnancies.
Around 28 percent of cases showed no clinical risk, with unexplained outcomes especially pronounced at later gestational ages. For instance, at week 40 or beyond, 40 percent of stillbirths had no discernible associated risk.
Socioeconomic Disparities Persist In Stillbirth Rates
The burden of stillbirths was most severe in low-income areas and regions with higher proportions of Black families. Families in poorer neighborhoods saw rates as high as one in every 112 births, while areas with more Black families experienced rates of one in 95 births.
These disparities highlight critical gaps in maternal health and healthcare equity across the nation.
Obstetric and Fetal Risk Factors Identified
The research identified several clinical risks for stillbirth. These include low or excess amniotic fluid, fetal anomalies, chronic hypertension, and a history of adverse pregnancy outcomes. However, nearly half of stillbirths at 37 weeks gestation or later are thought to be preventable. This intensifies calls for improved screening and intervention strategies.
Urgent Need For Better Prevention And Policy Change
Researchers stress the importance of advancing stillbirth risk prediction, addressing social determinants of health, and ensuring equitable obstetric care. Improved screening tools and greater focus on at-risk communities are imperative for reducing the stillbirth rate nationwide. Continued research is needed to explain many cases that occur without warning. Efforts are also required to close persistent gaps across income and race.
