Vaginal birth confers an 8-fold increase in the risk for a woman developing prolapse, a condition that results in 200,000 operations per year and carries up to a 25% reoperation rate at 10 years. Two primary causes for prolapse have emerged: 1) descent of the cervix and upper vagina (apical descent) involving the cardinal/uterosacral ligaments, and 2) neuromuscular damage to the levator ani muscles during vaginal birth. The relationship between these factors is unknown. It is the overall goal of our research to discover the basic mechanism whereby muscle and ligament failure interact producing prolapse. Our theoretical work suggests the working hypothesis that levator damage leads to opening of the levator urogenital hiatus and results in exposure of the vaginal wall to a pressure differential that pulls downward on the apical supports. Lack of data concerning ligament stiffness prevents a quantitative understanding of these relationships. We will recruit and test 50 asymptomatic volunteers and 50 women with pelvic organ prolapse to accomplish the following aims.
Aim 1 will use a new servoactuator device to measure the in vivo ligament force-displacement behavior (""""""""stiffness"""""""") to determine the role of different ligament properties in prolapse.
Aim 2 will make static and dynamic MRI images and clinical pelvic floor measurements to establish the relative contribution to apical descent by a) muscle impairment b) ligament properties.
Aim 3 will create subject-specific 3D models of the cardinal and uterosacral ligaments, which will be used to and determine the measurement differences in cardinal and uterosacral elongation in apical descent. The results of this study will provide data that can lead to clinically relevant tests to, for example, identify which patients need an operation to support the apex. It will also provide the much needed data, validating an overall disease model concerning interactions between ligament support and muscle damage. This research will be helpful in developing strategies for improved prevention and treatment selection and a better understanding of why muscle damage at birth causes prolapse later in life.

Public Health Relevance

Pelvic floor disorders represent a hidden epidemic of distressing problems women suffer due to their unique sex-differences in reproduction. The mechanistic insights from this proposed research will help to define the relationship between injuries that occur at birth and how they play a role in pelvic organ prolapse. These insights are needed to help prevent these disabling conditions and to open new avenues to personalized treatment and improved prevention.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Specialized Center (P50)
Project #
5P50HD044406-12
Application #
8549847
Study Section
Special Emphasis Panel (ZRG1-EMNR-Q)
Project Start
2013-06-01
Project End
2017-05-31
Budget Start
2013-06-01
Budget End
2014-05-31
Support Year
12
Fiscal Year
2013
Total Cost
$161,800
Indirect Cost
$79,445
Name
University of Michigan Ann Arbor
Department
Type
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Swenson, Carolyn W; Morgan, Daniel M; George, Jenny et al. (2018) Effect of Cystocele Repair on Cervix Location in Women With Uterus In Situ. Female Pelvic Med Reconstr Surg 24:56-59
Huebner, Markus; DeLancey, John O L; Reisenauer, Christl et al. (2018) Magnetic resonance imaging of vaginal support structure before and after Vecchietti procedure in women with Mayer-Rokitansky-Küster-Hauser syndrome. Acta Obstet Gynecol Scand 97:830-837
Masteling, Mariana; Ashton-Miller, James A; DeLancey, John O L (2018) Technique development and measurement of cross-sectional area of the pubovisceral muscle on MRI scans of living women. Int Urogynecol J :
Tracy, Paige V; Wadhwani, Shreya; Triebwasser, Jourdan et al. (2018) On the variation in maternal birth canal in vivo viscoelastic properties and their effect on the predicted length of active second stage and levator ani tears. J Biomech 74:64-71
Sammarco, Anne G; Swenson, Carolyn W; Kamdar, Neil S et al. (2018) Rate of Pelvic Organ Prolapse Surgery Among Privately Insured Women in the United States, 2010-2013. Obstet Gynecol 131:484-492
Berger, Mitchell B; Kolenic, Giselle E; Fenner, Dee E et al. (2018) Structural, functional, and symptomatic differences between women with rectocele versus cystocele and normal support. Am J Obstet Gynecol 218:510.e1-510.e8
Tracy, Paige V; Wineman, Alan S; Orejuela, Francisco J et al. (2018) A constitutive model description of the in vivo material properties of lower birth canal tissue during the first stage of labor. J Mech Behav Biomed Mater 79:213-218
Sammarco, Anne G; Nandikanti, Lahari; Kobernik, Emily K et al. (2017) Interactions among pelvic organ protrusion, levator ani descent, and hiatal enlargement in women with and without prolapse. Am J Obstet Gynecol 217:614.e1-614.e7
Harris, John A; Sammarco, Anne G; Swenson, Carolyn W et al. (2017) Are perioperative bundles associated with reduced postoperative morbidity in women undergoing benign hysterectomy? Retrospective cohort analysis of 16,286 cases in Michigan. Am J Obstet Gynecol 216:502.e1-502.e11
DeLancey, John O L (2017) ""Mommy, how will the baby get out of your tummy? Will it hurt you?"" Am J Obstet Gynecol 217:110-111

Showing the most recent 10 out of 127 publications