Want to Lower Preterm Birth Rates? Spend More on Social Programs

States that spent more on social programs tended to have lower rates of preterm birth, especially among infants of Black mothers, a cross-sectional study revealed.

Greater total state social expenditures were associated with lower rates of preterm birth, with an adjusted prevalence ratio (aPR) of 0.99 for every increase of $1,000 per low-income person (95% CI 0.97-0.999), though not with rates of low birth weight, reported Lawrence Chang, MD, of the University of California San Francisco, and colleagues.

Secondary analyses revealed that spending more on social expenditures particularly helped Black mothers and reduced their preterm birth rates (aPR 0.96, 95% CI 0.92-0.999). State expenditures that were most strongly associated with lower preterm birth rates for Black mothers were cash assistance and housing and community development (aPR 0.64, 95% CI 0.43-0.94 and aPR 0.91, 95% CI 0.84-0.98, respectively), authors wrote in JAMA Pediatrics.

“The reductions in preterm birth associated with greater social expenditures may appear modest,” the researchers wrote. “However, given that progress in reducing preterm birth nationally has been limited and even reversed in recent years, even a small reduction could represent a noteworthy policy impact for this challenging public health problem.”

Preterm birth has been on the rise in the U.S. since 2014. Both preterm birth and low birth weight are influenced by socioeconomic factors, such as poverty, which disproportionately impact Black mothers. The authors noted that preterm birth contributes to a third of infant deaths as well as a myriad of health issues, and they argue that “prevention of preterm birth through social investments may also carry substantial downstream benefits over the life course.”

Ultimately, the authors found that every $1,000 spent on social programs was linked to a 1.4% overall reduction in preterm birth rates and a 4.3% reduction for Black women specifically. The authors also recommended that “targeted investments toward cash assistance and housing development should be considered among policy interventions to advance equity in infant health.”

In an accompanying editorial, Scott Lorch, MD, of Children’s Hospital of Philadelphia, and colleagues pointed out that studying the impacts of public policy is tricky and “there is little information to help guide policymakers, advocates, or clinicians on the population health impact of such programs.” However, this study “provides some evidence that state-level policies may influence pregnancy and newborn outcomes.”

Still, Lorch and colleagues said this study does not definitively prove that more childcare support will inherently lower a person’s risk of preterm birth.

They said this study has issues similar to other ecological studies — like not accounting for “the presence of other policies or measures of community economic and environmental health that may influence health outcomes.”

This concerned the editorialists because “the selected population covariates in this study — i.e., poverty rate, unemployment rate, teenage pregnancy, and educational status — were assessed at the state level even though these characteristics vary widely within a given state.” Lorch called for a “contextually driven approach” for policy analysis that would incorporate factors that “can be used to determine fit between the intervention and the community’s needs and capacity or resources and inform needed adaptations.”

Researchers conducted a cross-sectional, ecological study among liveborn infants in all 50 U.S. states from January 1, 2011, through December 31, 2019. In this time period, there were 35.1 million live births in the U.S.; 3.4 million (9.8%) were preterm and 2.8 million (8.1%) were low birth weight. There were 5.2 million infants born to Black mothers, of which 709,332 (13.6%) were preterm and 700,951 (13.5%) were low birth weight. Among 18.7 million white babies, 1.7 million (9.1%) were preterm and 1.3 million (7.0%) were low birth weight.

The primary outcome was the yearly state-level rates of preterm birth (gestational age <37 weeks) as well as low birth weight (<2,500 g). The primary exposures were yearly expenditures by state and local governments on social programs, specifically state refundable earned income tax credits, cash assistance, childcare assistance, housing and community development, and public health.

Data came from the National Center for Health Statistics via the CDC’s Wide-ranging Online Data for Epidemiologic Research online databases. Government expenditure data came from the Internal Revenue Service and state departments of revenue, as well as from Temporary Assistance for Needy Families, the Child Care and Development Fund, Medicaid, and the Children’s Health Insurance Program.

On average, states spent $1,546 per low-income person, with roughly $53 on cash assistance, $106 on childcare assistance, $433 on housing and community development, and $825 on public health.

Study limitations include the cross-sectional study design and state-by-state variation and confounders. Also, misclassification or errors in the reporting of expenditures were possible. Lastly, they only evaluated spending for specific programs.