Researchers Investigate an Immune-System Mechanism Behind Some Preterm Births

Preterm birth occurs when a baby is born before 37 completed weeks of pregnancy. Babies born prematurely may face breathing difficulties, feeding problems and other complications because their organs have not completed development.

Inflammation plays a role in the body's immune response, but excessive inflammation can affect the uterus and placenta. The reported study investigated antibodies that interfere with IL-1RA, a protein that helps limit signalling by the inflammatory molecule IL-1 beta.

Researchers found that some women who delivered prematurely had elevated levels of these antibodies earlier in pregnancy. In mouse experiments, the antibodies increased inflammatory activity and caused placental damage resembling changes observed in human preterm deliveries.

The findings point to a possible mechanism affecting only a subset of pregnancies. Further research must determine how often this pathway contributes to preterm birth, whether it can be identified reliably and whether an intervention could prevent early labour safely.

The findings do not establish a new preventive treatment. Pregnant people should continue routine prenatal care and promptly contact their maternity-care team about contractions, bleeding, fluid leakage or other concerning symptoms.