Prediction of Uterine Atony After Vaginal Delivery by Elastography

Study Overview
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Brief Summary
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Prospective study evaluating the feasibility of shear-wave elastography of the uterus during the third stage of labour and following placental delivery. The investigators hypothesize that the stiffness of the myometrium can be measured by using shear-wave technology. This study involves 30 patients with a healthy pregnancy and spontaneous vaginal delivery. One co-investigator will carry out measurements at the uterine fundus, at three different time points: after fetal delivery, after placental delivery and 30 minutes after placental delivery.

Official Title
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Prediction of Uterine Atony After Vaginal Delivery by Shear Wave Elastography: a Feasibility Study

Conditions
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Postpartum Hemorrhage

Intervention / Treatment
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* Diagnostic Test: Shear wave elastography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: singleton pregnancy cephalic presentation maternal age > 18 years old nulliparous healthy uncomplicated pregnancy gestational age between 37-42 weeks of gestation spontaneous labour and delivery uncomplicated progression of labour (cervical dilatation at >1 cm/h) administration of less than 3 units of oxytocin during the second stage of labour patient having read, accepted and signed the consent form Exclusion Criteria: antepartum hemorrhage in the present pregnancy protracted second stage of labour (more than two hours from full dilatation to delivery) more than 30 minutes of active pushing BMI > 35 kg/m2 distance from skin to uterus > 8 cm age > 35 years old instrumental deliveries bleeding disorders polyhydramnios diabetes pre-eclampsia high blood pressure use of anticoagulant medications clinical chorioamnionitis placental abnormality (low-lying or abruption) fetal macrosomia uterine fibroids uterine anomalies previous uterine scar multiple pregnancy placental retention inability to follow procedures or insufficient knowledge of project language inability to give consent refusal to participate

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Female

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Shear wave elastography|Investigate the feasibility of use of shear-wave elastography of the uterus during the third stage of labour and following placental delivery in order to predict uterine atony .|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Stiffness of the myometrium | Difference in median myometrial shear wave velocity between each time point: after fetal delivery, after placental delivery and 30 minutes after placental delivery. | Third labor stage to 30 minutes post placenta delivery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood loss | Measurement of total blood loss | Two hours following the childbirth | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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postpartum hemorrhage, uterine atony, shear wave, elastography