Prevention of Per-partum Fetal Hypoxia: Measure of Placental Elasticity and Viscosity During Labor

Study Overview
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Brief Summary
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Fetal heart rate (FHR) monitoring during labor aims to detect fetuses at risk of intrapartum hypoxia in order to accelerate their birth before the constitution of sequelae such as anoxic encephalopathy and cerebral palsy. But the positive predictive value of FHR monitoring is low, and many second-line tests have been proposed but none of them has been proven to be conclusive. Measure of placental elasticity and viscosity during labor could be a new second line test to complete the FHR monitoring. Several studies have shown that placental elasticity is increased in case of gestational diabetes, preeclampsia, or intrauterine growth restriction, but no study has focused on placental elasticity during labor. The investigators hypothesize that placental elasticity and viscosity could reflect the quality of maternal-fetal exchanges during labor, and could help to detect fetus at risk of intrapartum hypoxia. The first aim of this study is to describe the values of placental elasticity and viscosity during different points in the labor: beginning of the labor, beginning of the active phase of the first stage of labor, and passive phase of the second stage of labor. Secondary aims of this study are: to describe the values of placental elasticity and viscosity in case of oxytocin infusion, in case of abnormal FHR, and ex-vivo after placental expulsion. This unicentric observational prospective study will include 150 patients with singleton pregnancy, without pathology, with spontaneous labor at term.

Official Title
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Prevention of Per-partum Fetal Hypoxia: Measure of Placental Elasticity and Viscosity During Labor

Conditions
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Placental Elastography, Fetal Monitoring

Intervention / Treatment
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* Other: Sonographic measure of placental elasticity and viscosity


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: singleton pregnancy spontaneous labor at term body mass index < 30 at the beginning of the pregnancy anterior, lateral or fundal placenta epidural analgesia at the beginning of the labor normal fetal heart rate at the beginning of the labor Exclusion Criteria: gestational diabetes preeclampsia intrauterine growth restriction

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Interventional Model Description: Sonographic measure of placental elasticity and viscosity
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: All the patients<br>Sonographic measure of placental elasticity and viscosity | Other: Sonographic measure of placental elasticity and viscosity<br>* Sonographic measure of placental elasticity and viscosity<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Placental elasticity in kilopascals (kPa) | beginning of the labor | Day 1 | 
| Placental viscosity in Pascal.seconde (Pa.s) | beginning of the labor | Day 1 | 
| Placental elasticity in kilopascals (kPa) | beginning of the active phase of the first stage of labor | Day 1 | 
| Placental viscosity in Pascal.seconde (Pa.s) | beginning of the active phase of the first stage of labor | Day 1 | 
| Placental elasticity in kilopascals (kPa) | passive phase of the second stage of labor | Day 1 | 
| Placental viscosity in Pascal.seconde (Pa.s) | passive phase of the second stage of labor | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Placental elasticity in kilopascals (kPa) | in case of oxytocin infusion | Day 1 | 
| Placental viscosity in Pascal.seconde (Pa.s) | in case of oxytocin infusion | Day 1 | 
| Placental elasticity in kilopascals (kPa) | in case of abnormal FHR | Day 1 | 
| Placental viscosity in Pascal.seconde (Pa.s) | in case of abnormal FHR | Day 1 | 
| Placental elasticity in kilopascals (kPa) | ex-vivo after placental expulsion | Day 1 | 
| Placental viscosity in Pascal.seconde (Pa.s) | ex-vivo after placental expulsion | Day 1 |