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

R. Ann Word; Xiang-Hong Li; Michael Hnat; Kelley Carrick

doi:10.1055/s-2006-956777

Seminars in Reproductive Medicine, Table of Contents

Semin Reprod Med 2007; 25(1): 069-079
DOI: 10.1055/s-2006-956777

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

Abstract

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

Full Text

References

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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