Understanding and Reducing Persistent Racial Disparities in Preterm Birth: a Model of Stress-Induced Developmental Plasticity.

Preterm birth is a leading cause of neonatal mortality and is characterized by substantial racial disparities in the US. Despite efforts to reduce preterm birth, rates have risen and racial disparities persist. Maternal stress is a risk factor for preterm birth; however, often, it is treated as a secondary variable rather than a primary target for intervention. Stress is known to affect several biological processes leading to downstream sequelae. Here, we present a model of stress-induced developmental plasticity where maternal stress is a key environmental cue impacting the length of gestation and therefore a primary target for intervention. Black women experience disproportionate and unique maternal stressors related to perceived racism and discrimination. It is therefore not surprising that Black women have disproportionate rates of preterm birth. The downstream effects of racism on preterm birth pathophysiology may reflect an appropriate response to stressors through the highly conserved maternal-fetal-placental neuroendocrine stress axis. This environmentally sensitive system mediates both maternal stress and the timing of birth and is a mechanism by which developmental plasticity occurs. Fortunately, stress does not appear to be an all-or-none variable. Evidence suggests that developmental plasticity is dynamic, functioning on a continuum. Therefore, simple, stress-reducing interventions that support pregnant women may tangibly reduce rates of preterm birth and improve birth outcomes for all women, particularly Black women.