Key clinical point: Non-Hispanic black women in the United States have a fivefold increased risk for experiencing early preterm birth, at 28 weeks’ gestation or less.

Major finding: Being of non-Hispanic black race was the single strongest predictor of preterm birth (PTB) at less than 28 weeks’ gestation. The adjusted odds ratio (aOR) of 4.99 surpassed an interpregnancy interval under 1 year (aOR, 4.47), chronic hypertension (aOR 2.84), and prior history of preterm birth (aOR, 2.81).

Study details: Retrospective nationwide cohort study of non-Hispanic black women, non-Hispanic white women, and women who identify as non-Hispanic white and black who had high socioeconomic status and singleton pregnancies without anomalies.

Disclosures: The study was supported by the National Institutes of Health. The authors reported no conflicts of interest.