Study of the Platelet Function During the Last Month of Pregnancy

Study Overview
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Brief Summary
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The objective is to compare women's platelet answer in the last month of pregnancy to women old enough to procreate, no pregnancy and without hormonal treatment. The hypothesis of research is that the decrease of platelet answer in pregnant women could not only limit the occurence of embolic accidents but also explain the lowest incidence of the arterial thrombosis in comparison with the venous thrombosis.

Detailed Description
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This is a monocentric study comparing a group of pregnant women and a group of no pregnancy women. The goal of the present study is to determine the impact of pregnancy on platelet function. For this, the study propose to explore, in women in the last month of pregnancy, the ability of platelets to aggregate after activation by strong agonists but also their ability to adhere to a matrix and form thrombies. The study will include 30 pregnant and 30 no pregnancy control women, of childbearing age and not taking hormone therapy. From a blood sample, two types of examination will be implemented: A) In whole blood, we will evaluate the percentage of platelet adhesion to collagen matrix or fibrinogen and the volume of thrombies formed. B) In washed platelets and whole blood, we shall determine the percentage of aggregation after activation by different agonists and the amount of certain membrane markers of platelet activation. Furthermore, an assay of estradiol plasma will be made.

Official Title
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Study of the Platelet Function During the Last Month of Pregnancy

Conditions
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Pregnancy

Intervention / Treatment
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* Other: Blood sample


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Signature of the form of consent Absence of any physical or psychic pathology which can interfere with the normal realization of the study Group1 : Women in the last month of pregnancy Group 2 : Women old enough to procreate, no pregnancy and without hormonal treatment Exclusion Criteria: Thrombopenia (platelet numeration < 120 000 / mm3), Gestational diabet, Hormonal treatment : oestrogen-progestagen, progestagen, Selective Estrogen Receptor Modulator (SERM), inductors of ovulation, Anticoagulant and any medication which can intervene on the platelet function (AINS, antidepressants) Personal history of thromboembolic accident venous or arterial, Personal history of haemostasis disease Personal history of hepatic or renal disease Personal history of autoimmune disease.

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: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Pregnancy<br>Blood sample | Other: Blood sample<br>* In washed platelets and whole blood, study shall determine the percentage of aggregation after activation by different agonists and the amount of certain membrane markers of platelet activation. Furthermore, an assay of estradiol plasma will be made. In whole blood, study will evaluate the percentage of platelet adhesion to collagen matrix or fibrinogen and the volume of thrombies formed.<br>* Other names: Blood sample in pregnancy and no pregnancy women;|
| Experimental: No pregnancy<br>Blood sample | Other: Blood sample<br>* In washed platelets and whole blood, study shall determine the percentage of aggregation after activation by different agonists and the amount of certain membrane markers of platelet activation. Furthermore, an assay of estradiol plasma will be made. In whole blood, study will evaluate the percentage of platelet adhesion to collagen matrix or fibrinogen and the volume of thrombies formed.<br>* Other names: Blood sample in pregnancy and no pregnancy women;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| surface covered by platelets | Percentage of surface covered by platelets (using the software Metamorph) | baseline | 
| Volume of thrombies | Total volume of thrombies in μm3 (using the software Metamorph) | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Platelet aggregation | Percentage of platelet aggregation (whole blood and washed platelets) | baseline | 
| chemokine Platelet Factor 4 | Quantity of the chemokine Platelet Factor 4 (PF4) (IU/ml) secreted by the granules after activation by these agonists (washed platelets) | baseline | 
| Thromboglobulin | Quantity of thromboglobulin (in ng / ml) secreted by the granules after activation by these agonists (washed platelets) | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pregnancy, platelets