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Pathogenesis of spontaneous preterm birth

Charles J Lockwood, MD, MHCM
Section Editor
Susan M Ramin, MD
Deputy Editor
Vanessa A Barss, MD, FACOG


Preterm birth (PTB) is the leading cause of infant morbidity and mortality in the industrialized world (table 1). For this reason, the pathogenic processes leading to PTB and development of preventive interventions are major targets of obstetric research.

This topic will discuss the major pathogenic mechanisms that lead to PTB. Risk factors for PTB and risk reduction interventions are reviewed separately. (See "Preterm birth: Risk factors and interventions for risk reduction".)


Compelling clinical and research evidence suggest that a number of pathogenic processes can lead to a final common pathway that results in spontaneous PTB. The four primary processes are:

Premature activation of the maternal or fetal hypothalamic-pituitary-adrenal axis

Exaggerated inflammatory response/infection


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Literature review current through: Sep 2016. | This topic last updated: Sep 8, 2016.
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