Determination of Reference Values for Diluted Russell's Viper Venom Time (dRVVT) Specific to Pregnant Women (GRAPL)

Sponsor

Hospices Civils de Lyon (Other)

Overall Status

Not yet recruiting

CT.gov ID

NCT06133621

Collaborator

(none)

100

Enrollment

Anticipated Duration (Months)

Study Details

Study Description

Brief Summary

Pregnancy is associated with significant changes in several aspects of haemostasis, especially an imbalance between procoagulant and anticoagulant factors. These changes contribute to creating a state of hypercoagulability, mainly at the end of pregnancy and during the post-partum period, protecting pregnant women from delivery haemorrhage, but exposing them to a major thromboembolic risk.

Vascular diseases of pregnancy (VDP) are obstetric diseases which are linked to an ischaemic origin associated with placental thrombosis. These include pre-eclampsia, retroplacental haematoma, intrauterine growth retardation and even foetal death in utero. A number of risk factors have been identified for these VDPs, some of which have extremely serious consequences, the main one being antiphospholipid syndrome (APS).

The diagnosis of VDP in a current or previous pregnancy requires close monitoring and joint management by an obstetrician, haemostasis physician, internist and medical biologist, particularly in terms of pre, peri- and post-partum anticoagulation in patients at increased risk of thromboembolism.

The aim of treating APS during pregnancy is : to reduce the occurrence of maternal arterial or venous thrombotic complications in one hand and in the other hand to reduce the occurrence of obstetric complications, which are responsible of a significant morbimortality rate. The detection of a possible APS during pregnancy will therefore determine the specific management of patients.

The latest guidelines from the Groupe Français d'Etude sur l'Hémostase et la Thrombose (GFHT) in 2022 recommended a diluted Russell's viper venom time (dRVVT) and an activated partial thromboplastin time (APTT) measured using a sensitive reagent such as silica (SCT) should be used to assess the presence of LA.

Condition or Disease	Intervention/Treatment	Phase
Normal Pregnancy	Other: dosage dRVVT

Detailed Description

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Study Design

Study Type:

Observational

Anticipated Enrollment :

100 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

Thrombophilia Assessment and Pregnancy: Determination of Reference Values for dRVVT in Pregnant Women

Anticipated Study Start Date :

Jan 2, 2024

Anticipated Primary Completion Date :

Oct 2, 2024

Anticipated Study Completion Date :

Oct 2, 2024

Arms and Interventions

Arm	Intervention/Treatment
cases Patients treated at HCL who have had an increased dRVVT ratio during pregnancy, investigated in the context of the development of VDP during pregnancy	Other: dosage dRVVT Blood test dRVVT assay on two tubes of blood in the haemostasis laboratory of the Center de Biologie et de Pathologie Est
Controls Patients with normal pregnancies followed at the Croix Rousse maternity hospital	Other: dosage dRVVT Blood test dRVVT assay on two tubes of blood in the haemostasis laboratory of the Center de Biologie et de Pathologie Est

Arm

Intervention/Treatment

cases

Patients treated at HCL who have had an increased dRVVT ratio during pregnancy, investigated in the context of the development of VDP during pregnancy

Other: dosage dRVVT

Blood test dRVVT assay on two tubes of blood in the haemostasis laboratory of the Center de Biologie et de Pathologie Est

Controls

Patients with normal pregnancies followed at the Croix Rousse maternity hospital

Other: dosage dRVVT

Blood test dRVVT assay on two tubes of blood in the haemostasis laboratory of the Center de Biologie et de Pathologie Est

Outcome Measures

Primary Outcome Measures

dRVVT value during pregnancy. [through study completion, an average of 9 months]
Carrying out the dRVVT in the haemostasis laboratory of the Centre de Biologie et de Pathologie Est

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 50 Years

Sexes Eligible for Study:

Female

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Control group :

patients with normal pregnancies at the HCL.
Affiliation to a social security regime

Case group :

Patients followed at the HCL who had an increased dRVVT ratio during pregnancy, investigated as part of the development of VDP during pregnancy.
Affiliation to a social security regime