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Semin Reprod Med 2007; 25(1): 069-079
DOI: 10.1055/s-2006-956777
Copyright © 2007 by Thieme Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Dynamics of Cervical Remodeling during Pregnancy and Parturition: Mechanisms and Current Concepts

R. Ann Word1 , Xiang-Hong Li1 , Michael Hnat1 , Kelley Carrick2
  • 1Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, Texas
  • 2Department of Pathology, University of Texas Southwestern Medical Center, Dallas, Texas
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Publication History

Publication Date:
05 January 2007 (online)

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ABSTRACT

The cervix serves as a protective barrier from invading microorganisms and as a structural barrier to delivery of the fetus. Among all biological processes, the phenomenal connective tissue remodeling that occurs in the cervix during and after parturition is unparalleled in scope and magnitude. The process of connective tissue remodeling in the cervix during pregnancy occurs in four stages: softening, ripening, dilation, and repair. Although overlapping in time, each stage is uniquely regulated. Results from studies using serial measurements of cervical length indicate that cervical ripening precedes myometrial contractions of labor by several weeks, suggesting that parturition in women is a process of long duration and that uterine contractions of labor are late events in the parturition process. A clear understanding of the biologic mechanisms that regulate cervical remodeling during pregnancy is needed to influence the preterm birth rate and to develop strategies to prevent preterm dilation of the cervix.

KEYWORDS

Cervix - ripening - glycosaminoglycans - cervical dilation - matrix remodeling

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R. Ann WordM.D. 

Professor of Obstetrics & Gynecology, Divisions of Reproductive Endocrinology and Urogynecology, University of Texas Southwestern Medical Center

5323 Harry Hines Blvd., Dallas, TX 75390-9032

Email: Ruth.Word@UTSouthwestern.edu