Neonatal deaths in the US decline overall, but malnutrition-related mortality rises

Neonatal deaths in the US decline overall, but malnutrition-related mortality rises | Image Credit: © Sergey Novikov - stock.adobe.com.

A retrospective study analyzing over 2 decades of national data found that while overall US neonatal mortality from perinatal causes has declined, mortality from slow fetal growth and fetal malnutrition has increased annually, highlighting persistent disparities in neonatal outcomes.^1,2

The study, led by Khan et al, utilized data from the Centers for Disease Control and Prevention’s Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) between January 1, 1999, and December 31, 2022. Researchers focused on neonatal deaths due to perinatal complications, defined using International Classification of Diseases, Tenth Revision (ICD-10) codes P00 to P96. Standardized diagnostic groupings from the National Center for Health Statistics were used to identify and stratify the 10 leading causes of neonatal death over the study period. Mortality rates were further analyzed by sex, delivery method, birthplace, and age at death. Joinpoint regression modeling was used to assess trends, with statistical significance set at P < .05.

A total of 283,696 neonatal deaths were reported during the study period, with males accounting for 56.2% (n = 159,445) of deaths. The top 10 causes represented 79.8% (n = 226,323) of all deaths. The leading cause was disorders related to short gestation and low birth weight, with a crude mortality rate (CR) of 102.10 per 100,000 live births. Other major contributors included maternal complications of pregnancy (CR, 37.71), complications of the placenta, cord, and membranes (CR, 23.39), and bacterial sepsis of the newborn (CR, 15.88).

Most causes showed a significant decline over time. The largest reduction was observed in deaths due to interstitial emphysema and related conditions, with an annual average percent change (AAPC) of −5.40% (95% CI, −6.20% to −4.64%). Mortality from respiratory distress originating in the perinatal period also declined significantly (AAPC, −3.63%; 95% CI, −4.45% to −3.00%).

Conversely, mortality from slow fetal growth and fetal malnutrition rose by 1.91% per year (95% CI, 0.46% to 3.82%). Mortality rates related to maternal complications (AAPC, −0.35%; 95% CI, −1.04% to 0.29%) and bacterial sepsis (AAPC, −0.24%; 95% CI, −0.57% to 0.14%) remained statistically stable over time.

According to the authors, “US neonatal mortality has generally decreased, likely due to medical advancements, improved prenatal care, and neonatal intensive care interventions.” However, they noted that the rise in deaths from malnutrition “may reflect impaired prenatal nutrition.”

Disparities were also noted by sex and delivery method. Male neonates consistently experienced higher mortality, possibly due to “differences in lung development and immune response.” Vaginal deliveries were associated with nearly three times the mortality rate of cesarean deliveries, which may be linked to complications such as “birth trauma and prolonged labor.”

Additionally, sepsis-related deaths were most common between days 1 and 28 of life, often associated with prematurity. While deaths from interstitial emphysema declined in hospital births, births occurring outside of hospital settings had a higher risk of neonatal death, likely due to “inadequate delivery management.”

The study authors acknowledged several limitations, including the inability to assess key nutritional exposures such as breastfeeding, exclusion of congenital malformations to focus on perinatal causes, and limitations related to assigning a single ICD-10 code per death, which may not capture coexisting conditions. “Some ICD-10 blocks grouped pathophysiologically distinct conditions… which may affect interpretation,” the authors wrote. The transition between versions of the US Standard Certificate of Live Birth across states also posed challenges in data consistency during earlier years of the study.

The authors concluded that while progress in neonatal mortality reduction is evident, targeted strategies are needed to address persistent risks associated with fetal malnutrition, delivery practices, and nonhospital births.

References:

1. Khan M, Nabi W, Aziz N, et al. US Neonatal Mortality From Perinatal Causes. JAMA Pediatrics. Published online June 23, 2025. doi:https://doi.org/10.1001/jamapediatrics.2025.1710
2. Centers for Disease Control and Prevention. Maternal and infant health: an overview. CDC. 2024. Accessed July 11, 2025. https://www.cdc.gov/maternal-infant-health/about/index.html

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