Assessing the Stability of Uterine Scar Tissue in Women With Previous History of Caesarean Section Using Multimodal Analyses of the Lower Uterine Segment Including Quantitative Sonography

Study Overview
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Brief Summary
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This prospective, clinical, observational trial compares the measured value with quantitative ultrasonic (preoperatively) Elastic modulus E (kPA) with the measured value with quantitative ultrasonic Elastic modulus E (kPA) in vitro (postoperatively) and with the experimental measurement done in vitro (postoperatively) of lower uterine segment of women who underwent second cesarean section.

Detailed Description
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In 1991, 126.297 (15.3%) women delivered by caesarean section in Germany. Since then, the rate of caesarean section increased steadily over the next 20 years, reaching up to 32.2% in 2011. The absolute risk of uterine rupture in vaginal birth after Caesarean section is 1 in 100 deliveries. The risk of perinatal death or the outcome of extremely neurological impairment is 1 in 1000 deliveries. Statistically more than 300 pregnant women with a prior caesarean delivery visit daily ultrasound departments of german hospitals to investigate the C-section scar before delivery. They have one important question: Is it possible to predict successful trial of labor after cesarean delivery? The information for the risk of uterine rupture remains insufficient based only on ultrasonography assessment. What are the possibilities of additional parameters to examine the stability of uterine scar tissue? Currently, there is no defined cut-off value of scar thickness for the prediction of uterine rupture. It remains questionable whether the thickness of the lower uterine segment is the determinant factor for the stability of the scar and the probability of rupture. However, another important factor is the functional elasticity or the structure of the connective tissue. It has not been further investigated until now (both quantitatively and qualitatively). Objective of this project: Multimodalities of assessments, including ultrasonography and elastography, validate the accuracy of uterine scar stability in women with previous history of Caesarean section in vitro and in vivo.

Official Title
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Multimodale Beurteilung Der Stabilität Von Uterusnarbengewebe Bei Z.n. Sectio Caesarea

Conditions
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Scar; Previous Cesarean Section

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: pregnancy after previous cesarean section pregnancy between 37 0/7 and 42 0/7 weeks of gestation primary or secondary indication for cesarean section ability to give informed consent in german or english Exclusion Criteria: emergency caesarean section <18 years old

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| In vitro Ultrasonic Elastic Modulus versus in vitro tensile property measurements of LUS | The measured value of lower uterine segment with quantitative ultrasonic Elastic modulus E (kPA) in vitro versus the experimental tensile property measurements of lower uterine segment done in vitro. (Spearman's rank correlation coefficient) | within 1 hour after Cesarean Section | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference - In vivo Ultrasonic Elastic Modulus versus in vitro tensile property measurements of LUS | The measured value of lower uterine segment with quantitative ultrasonic (preoperatively) Elastic modulus E (kPA) in vivo versus the experimental tensile property measurements of lower uterine segment done in vitro (postoperatively). (Spearman's rank correlation coefficient) | within 1 hour after Cesarean Section | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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repeat cesarean section, lower uterine segment, quantitative sonography