Factor V Leiden Heterozygous MutationPOSTPART AS5-2NCT07342127
Evaluation of a Preventive Therapeutic Strategy for Postpartum Venous Thromboembolism in Women With Genetic Risk Factor
An observational study of Factor V Leiden Heterozygous Mutation and Factor II Heterozygous Mutation, run by Hospices Civils de Lyon at 2 sites in France.
Trial summary
Background : pregnancy and postpartum period are times of increased risk for deep vein thrombosis (DVT). The incidence of venous thromboembolic disease (VTE) during pregnancy is estimated at 1-2 per 1,000, and this risk increases in the postpartum period, rising up to 80-fold. Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- Factor V Leiden Heterozygous Mutation, Factor II Heterozygous Mutation, Pregnancy
- What is being tested?
- Retrospective collection of health data and Phone call to every participant
- How many people
- 86 participants
- Where
- 2 sitesFrance
- Study dates
- 4 Feb 2026to 13 Mar 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Study population: Female patients over than 18 years old, carrying asymptomatic heterozygous Factor V Leiden or Factor II mutation ; who consulted in Hospices Civils de Lyon for this condition, and who delivered between 01/01/2020 and 31/12/2026.
Who may be able to join
- Age > 18
- Heterozygous asymptomatic Factor V Leiden mutation or Factor II mutation, diagnosed before or during pregnancy
- Delivering between 01/01/2020 and 31/12/2025
- Patient with French social security rights
Who cannot join
- NA
Trial locations and contacts
2 sites in 1 country.
France2 sites
Service d'hémostase clinique - Hôpital Louis Pradel
Bron, 69500
Service Gynécologie Obstétrique - Hôpital de la Croix Rousse
Lyon, 69004
About this study
Official title: Evaluation of a Preventive Therapeutic Strategy for Postpartum Venous Thromboembolism in Asymptomatic Women With Heterozygous Factor V Leiden ou Factor II Mutation.
Background : pregnancy and postpartum period are times of increased risk for deep vein thrombosis (DVT).
The incidence of venous thromboembolic disease (VTE) during pregnancy is estimated at 1-2 per 1,000, and this risk increases in the postpartum period, rising up to 80-fold. VTE is a multifactorial condition, and several studies have identified risk factors for DVT during this period. These factors may be related to the patient herself-such as age, overweight, smoking, a personal or family history of DVT, and/or thrombophilia. Factors related to the pregnancy itself and peripartum events-such as preeclampsia, multiple pregnancy, the mode of delivery (emergency or elective cesarean section), and postpartum hemorrhage-have also been identified as DVT risk factors.
Read more
Resistance to activated protein C caused by the Factor V Leiden mutation affects about 5% of the population and, in its heterozygous form, increases the risk of VTE by 3- to 10-fold depending on the study, raising the absolute risk to approximately 1 in 400. The heterozygous mutation of the prothrombin (Factor II) gene affects about 2% of the population and increases the risk of VTE threefold. However, although the risk is increased, the absolute risk of VTE remains low (0.5 to 1%).
Regarding prevention, recommendations are heterogeneous and often based on a low level of evidence. In certain situations (e.g., history of provoked thrombosis, moderate thrombophilia), prophylaxis is not always recommended, or its duration is not clearly defined, and the benefit-risk balance remains uncertain.
The main objective of this study is to describe the duration of anticoagulation prescribed after delivery according to the characteristics of patients carrying these mutations and their mode of delivery. The secondary composite objective is to compare two treatment durations (less than 2 weeks vs. 6 weeks) to determine whether a shorter treatment is less effective in preventing deep vein thrombosis, and whether a longer treatment is associated with more adverse effects.
The target population therefore consisted of adult women carrying an asymptomatic heterozygous mutation of Factor V or Factor II, who had been followed up or had consulted at the Hospices Civils de Lyon for obstetric or hematologic evaluation related to this mutation.
Investigators extracted health data of the included patients from the Hospices Civils de Lyon medical software. They also contacted patients by phone to complete data collection, particularly to determine whether they had experienced a deep vein thrombosis within 12 weeks after delivery, or any adverse effects related to anticoagulant therapy.
- Conditions
- Factor V Leiden Heterozygous Mutation, Factor II Heterozygous Mutation, Pregnancy, Postpartum
- Being tested
- Retrospective collection of health data, Phone call to every participant
- Keywords
- Veinous thromboembolism (VTE), Pregnancy, Postpartum, Thromboprophylaxis, Heterozygous factor V Leiden mutation, Prothrombin gene mutation, Thrombophilia, Low molecular weight heparin (LMWH)
- Medical subject headings
- Thrombophilia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Retrospective collection of health dataOther
From Hospices Civils de Lyon database, collection in Word Excel document of anonymized health data :
Age, contact details, medical history, first degree family medical history, smoking status, previous estroprogestative contraception utilization, number of gestation, number of miscarriages, any medically assisted reproduction, singleton ou multiple pregnancy, obstetrical complication such as preeclampsia or postpartum hemorrhage, due date, delivering mode, any procoagulant treatment administration, anesthesia, thromboprophylaxis treatment duration
Phone call to every participantOther
Phone call to every participant to assess any thromboembolic event in 12 first postpartum weeks, any treatment side effect, and their personal experience of the treatment
| Study group | Role | What they receive |
|---|---|---|
| 2 weeks or less postpartum thromboprophylaxis | Patients receiving 2 weeks (or less) preventive anticoagulation with low molecular weight heparin after giving birth Receives: Other: Retrospective collection of health data; Other: Phone call to every participant | |
| 6 weeks postpartum thromboprophylaxis | Patients receiving 6 weeks preventive anticoagulation with low molecular weight heparin after giving birth Receives: Other: Retrospective collection of health data; Other: Phone call to every participant |
What is being measured
The primary outcome is the main question the study is designed to answer.
Thromboprophylaxis treatment duration
Evaluation of the given thromboprophylaxis treatment duration according to patients' characteristics
Measured: At baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Jan 2026
- Study start4 Feb 2026
- Primary completion13 Mar 2026
- Study completion13 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Factor V Leiden Heterozygous MutationStudies of the same condition, open and under way.
- More trials run by Hospices Civils de LyonThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 86 participants (actual)
Sponsor and investigators
- Lead sponsor
- Hospices Civils de Lyon
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Lucia Rugeri, Principal investigator, Service de Gynécologie Obstétrique - Hôpital de la Croix Rousse
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07342127
- Sponsor's protocol ID
- 69HCL25_1157
- Other IDs
- 2025-A02800-49
- Acronym
- POSTPART AS5-2
- Status last verified
- Mar 2026
- First submitted
- 6 Jan 2026
- Last updated
- 6 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of a Preventive Therapeutic Strategy for Postpartum Venous Thromboembolism in Asymptomatic Women With Heterozygous Factor V Leiden ou Factor II Mutation.
- ClinicalTrials.gov ID
- NCT07342127
- Acronym / sponsor ID
- POSTPART AS5-2 / 69HCL25_1157
- Conditions
- Factor V Leiden Heterozygous Mutation, Factor II Heterozygous Mutation, Pregnancy, Postpartum
- Keywords
- Veinous thromboembolism (VTE), Pregnancy, Postpartum, Thromboprophylaxis, Heterozygous factor V Leiden mutation, Prothrombin gene mutation, Thrombophilia, Low molecular weight heparin (LMWH)
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 86 participants (actual)
- Lead sponsor
- Hospices Civils de LyonUniversity, hospital or other
- Study start
- 4 Feb 2026 (actual)
- Primary completion
- 13 Mar 2026 (actual)
- Study completion
- 13 Mar 2026 (actual)
- First posted
- 15 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Background : pregnancy and postpartum period are times of increased risk for deep vein thrombosis (DVT).
The incidence of venous thromboembolic disease (VTE) during pregnancy is estimated at 1-2 per 1,000, and this risk increases in the postpartum period, rising up to 80-fold. VTE is a multifactorial condition, and several studies have identified risk factors for DVT during this period. These factors may be related to the patient herself-such as age, overweight, smoking, a personal or family history of DVT, and/or thrombophilia. Factors related to the pregnancy itself and peripartum events-such as preeclampsia, multiple pregnancy, the mode of delivery (emergency or elective cesarean section), and postpartum hemorrhage-have also been identified as DVT risk factors.
Resistance to activated protein C caused by the Factor V Leiden mutation affects about 5% of the population and, in its heterozygous form, increases the risk of VTE by 3- to 10-fold depending on the study, raising the absolute risk to approximately 1 in 400. The heterozygous mutation of the prothrombin (Factor II) gene affects about 2% of the population and increases the risk of VTE threefold. However, although the risk is increased, the absolute risk of VTE remains low (0.5 to 1%).
Regarding prevention, recommendations are heterogeneous and often based on a low level of evidence. In certain situations (e.g., history of provoked thrombosis, moderate thrombophilia), prophylaxis is not always recommended, or its duration is not clearly defined, and the benefit-risk balance remains uncertain.
The main objective of this study is to describe the duration of anticoagulation prescribed after delivery according to the characteristics of patients carrying these mutations and their mode of delivery. The secondary composite objective is to compare two treatment durations (less than 2 weeks vs. 6 weeks) to determine whether a shorter treatment is less effective in preventing deep vein thrombosis, and whether a longer treatment is associated with more adverse effects.
The target population therefore consisted of adult women carrying an asymptomatic heterozygous mutation of Factor V or Factor II, who had been followed up or had consulted at the Hospices Civils de Lyon for obstetric or hematologic evaluation related to this mutation.
Investigators extracted health data of the included patients from the Hospices Civils de Lyon medical software. They also contacted patients by phone to complete data collection, particularly to determine whether they had experienced a deep vein thrombosis within 12 weeks after delivery, or any adverse effects related to anticoagulant therapy.
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| 2 weeks or less postpartum thromboprophylaxis | – | Other: Retrospective collection of health data, Other: Phone call to every participantPatients receiving 2 weeks (or less) preventive anticoagulation with low molecular weight heparin after giving birth |
| 6 weeks postpartum thromboprophylaxis | – | Other: Retrospective collection of health data, Other: Phone call to every participantPatients receiving 6 weeks preventive anticoagulation with low molecular weight heparin after giving birth |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Female patients over than 18 years old, carrying asymptomatic heterozygous Factor V Leiden or Factor II mutation ; who consulted in Hospices Civils de Lyon for this condition, and who delivered between 01/01/2020 and 31/12/2026.
Key inclusion criteria (4 listed)
- Age > 18
- Heterozygous asymptomatic Factor V Leiden mutation or Factor II mutation, diagnosed before or during pregnancy
- Delivering between 01/01/2020 and 31/12/2025
- Patient with French social security rights
Key exclusion criteria (1 listed)
- NA
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Retrospective collection of health dataFrom Hospices Civils de Lyon database, collection in Word Excel document of anonymized health data : Age, contact details, medical history, first degree family medical history, smoking status, previous estroprogestative contraception utilization, number of gestation, number of miscarriages, any medically assisted reproduction, singleton ou multiple pregnancy, obstetrical complication such as preeclampsia or postpartum hemorrhage, due date, delivering mode, any procoagulant treatment administration, anesthesia, thromboprophylaxis treatment duration | Other | 2 weeks or less postpartum thromboprophylaxis, 6 weeks postpartum thromboprophylaxis |
| Phone call to every participantPhone call to every participant to assess any thromboembolic event in 12 first postpartum weeks, any treatment side effect, and their personal experience of the treatment | Other | 2 weeks or less postpartum thromboprophylaxis, 6 weeks postpartum thromboprophylaxis |
Primary outcome
Thromboprophylaxis treatment duration
Time frame: At baseline
Evaluation of the given thromboprophylaxis treatment duration according to patients' characteristics
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Apr 2026.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Lucia Rugeri principal investigator
Service de Gynécologie Obstétrique - Hôpital de la Croix Rousse
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Factor V Leiden Heterozygous Mutation and Factor II Heterozygous Mutation, run by Hospices Civils de Lyon at 2 sites in France.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Thromboprophylaxis treatment duration (time frame: At baseline). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Apr 2026.