An interventional study of Lyon-VTE score and recommendations currently available in Thromboembolism and Pregnancy, sponsored by Hospices Civils de Lyon. Recruiting at 1 site in France. Open to participants aged 18 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-05-15.
Sponsored by Hospices Civils de Lyon · Not applicable, Interventional, and Prevention
The management of venous thromboembolism (VTE) risk in pregnancy still remains a challenge. An individual assessment of the VTE risk is crucial for optimal thromboprophylaxis, but there is no validated tool to help clinicians stratify the risk in pregnant women and introduce prophylactic anticoagulation at the appropriate time. Recommendations mostly based on case-control studies and expert opinions do not accurately reflect the physician's need. In view of the lack of international recommendations with a high level of evidence regarding prophylactic treatment of pregnant women at risk of thrombosis, the use of a risk stratification tool that takes all individual risk factors for VTE into consideration and which aids decisions over prophylaxis regimens may help. Investigators have previously described a VTE risk score (the Lyon-VTE-score), rating patients at increased risk of VTE and recommending individually tailored management. A retrospective evaluation of the initial score showed favorable outcomes in pregnancies with a high risk of thrombosis. A subsequent multicenter prospective study reported promising results using this score and related management strategy. The efficacy and safety after 10 years of prospective use of the Lyon-VTE-score in daily practice to guide the prescription of antithrombotic prophylaxis during pregnancy was recently evaluated and the results showed that the Lyon-VTE-score allows a standardized approach with objective criteria and can help non-specialized centers and young doctors manage these high-risk pregnancies.
The results of previous studies provide consistent conclusions on the safety and efficacy of the approach of investigators and give background for a medico-economic study to evaluate costs and consequences of this procedure. The most recent study (2005) evaluating the cost of prophylaxis in pregnant women, evaluated this cost as $1292 for each 6-week cycle of treatment. In addition, the use of such a score offers the prospect of personalized medicine, which is probably more cost-efficient compared to "inclusive, equal treatment for all".
In antepartum, the decision to administer thromboprophylaxis should be considered on an individual basis with regard to lowering the absolute risk of thrombosis, the inconvenience of daily subcutaneous heparin therapy and the potential risks of bleeding, heparin-induced thrombocytopenia and osteoporosis. An individual assessment of the VTE risk is crucial for optimal thromboprophylaxis, but there is no validated tool to help clinicians to stratify VTE risk in pregnant women and to introduce prophylactic anticoagulation at the right time.
Most of the recommendations are grade 2C. They are mostly based on case-control studies and expert opinions and do not entirely highlight the physicians' need. The originality of this approach is the use of a risk stratification tool that takes all individual risk factors for VTE into consideration and that aids the decision-making process of antenatal anti-thrombotic prophylaxis. This study will personalize care using a score to individually assess the risk and propose appropriate prevention.
The main objective of this study is to conduct a medico-economic study to evaluate the efficiency of an innovative strategy integrating the Lyon-VTE-score in the management of pregnant patients with venous thromboembolism risk versus standard care.
712 studies on the registry are indexed under Venous Thromboembolism; 146 are open to participants now.
This study's planned enrollment of 600 is above the median of 240 across 401 interventional studies indexed under Venous Thromboembolism.
Browse Venous Thromboembolism studies →Hospices Civils de Lyon is the lead sponsor of 1,866 studies on the registry; 448 are open to participants now.
Compared within Venous Thromboembolism, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Thromboembolism. The counts are of registry records indexed under each term, refreshed daily. How we classify →
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Exclusion Criteria:
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A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
300 adult pregnant women with a personal history of VTE and/or known thrombophilia, will be randomly included in this group and their VTE risk during pregnancy will be managed according to the Lyon-VTE score : The Lyon score classifies patients into 3 risk categories and directs the preventive LMWH prescription: * A score strictly less than 3 indicates a moderate thrombotic risk: the patient does not receive LMWH in ante-partum; * A score between 3 and 5 indicates a high thrombotic risk: a preventive dose LMWH is introduced in the third trimester (from the beginning of the 7th month); * A score greater than or equal to 6 indicates a very high thrombotic risk: LMWH at a preventive dose is prescribed throughout the ante-partum. All patients receive an elasto-compression prescription and daily physical activity is recommended throughout pregnancy (except obstetric contraindication). All patients also receive systematic preventive LMWH treatment postpartum for 6 weeks.
Procedure: Lyon-VTE score
300 adult pregnant women with a personal history of VTE and/or known thrombophilia, will be randomly included in this group and their VTE risk during pregnancy will be managed according to the last ACCP guidelines or UK guidelines or Canadian recommendations or French recommendations, according to the habits of the center.
Procedure: recommendations currently available
follow-up at 3 months, 5 months, 7 months during pregnancy and 3 months and 12 months after delivery.
follow-up at 7 months during pregnancy and 3 months and 12 months after delivery.
cost-utility ratio
Medico-economical data related to the score-based management strategy will be collected during all pregnancy and at months 3 and 12 in the postpartum period.
Time frame: until 12 months after delivery
occurrence of venous thromboembolism
efficacy data related to the score-based management strategy will be collected during all pregnancy and at months 3 and 12 in the postpartum period
Time frame: until 12 months after delivery
occurrence of bleeding complications
safety data related to the score-based management strategy will be collected during all pregnancy and at months 3 and 12 in the postpartum period
Time frame: until 12 months after delivery
Evaluation of quality of life of pregnant women at high risk of thrombosis by the EQ-5D-3L survey
quality of life data will be collected during all pregnancy and at months 3 and 12 in the postpartum period using the EQ-5D-3L survey
Time frame: until 12 months after delivery
Started Jan 2021 (actual). Primary completion is estimated for Oct 2031, 129 months after the start.
Of 65 non-industry interventional studies with no phase under Venous Thromboembolism, half reached primary completion within 31 months of starting (the median), counting those still running; a quarter within 19 and three quarters within 57. This study's planned 129 months is above that.
Counting every sponsor, half of 70 studies reached it within 31 months; a quarter within 19 and three quarters within 57.
How these figures are worked out, and which studies are left out of them.
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