United States9,209 peptides set preterm mothers apart from 204 term controls.
Divergence appears in the first trimester, which points toward an early blood test.
Each standard deviation of antibody signal raised preterm odds 1.54-fold, largely independent of prior preterm birth, the study found.
On 466 held-out samples, the model scored 0.76 on a 1.0 accuracy scale, below its training performance.
The study does not test whether blocking these antibodies prevents early delivery.
Sources: Nature