The live birth of an infant with a gestational age of 36 weeks or less. While the birth of infants before term age runs in families, suggesting a hereditary component, the causes of a preterm birth are not properly understood. The most effective preventive treatment appears to be extensive bed rest during pregnancy for women with a high risk for premature delivery.
See Ascending genital tract infection, Biological risk factor, Corticotrophin-releasing hormone (CRH), Fetal programming, Hippocampus, Mesencephalic reticular activating system, Placenta previa, Preterm infant, Prospective cohort, Very (or extremely) preterm birth