SAFELY RULING OUT DEEP VEIN THROMBOSIS IN PREGNANCY WITH THE LEFt SCORE AND TRIMESTER-ADJUSTED D-DIMER CUTOFFS (the PREG-DVT Study): A PROSPECTIVE COHORT STUDY.

NCT07884981 | Not Yet Recruiting

• 1 other identifier: ooooo
• Study Type: interventional
• Target: 330
• Locations: 1 country
• Sites: 1

Brief Summary

Venous thromboembolism (VTE), which includes deep vein thrombosis and pulmonary embolism (PE), is a leading cause of maternal morbidity and mortality in high-income countries.1 DVT is suspected in pregnancy greater than 10 times more often than it is confirmed.2 The overlap between physiological symptoms of pregnancy (e.g. leg edema and calf, thigh and groin discomfort) and those of DVT often leads to referral for investigation of DVT, especially in later stages of pregnancy. DVT during pregnancy has a strong left leg predominance likely due to left iliac vein compression by the right iliac artery and the gravid uterus.3,4 Unfortunately, the only validated strategies to exclude DVT in pregnant patients require diagnostic imaging as the first step in the diagnostic algorithm. Specifically, compression ultrasonography (CUS), either as a single, whole-leg ultrasound2,5 or as a serial proximal ultrasound6 has been validated to exclude DVT during pregnancy. The LEFt clinical decision score-a simple three-item tool including Left leg symptoms, Edema (≥2 cm calf circumference difference compared to the other leg), and First trimester onset of symptoms-has shown promise in the LEFt derivation study6 and retrospective validation studies.7,8 More recently, the score was tested in a prospective study (LEAD study, OC, ISTH Congress, Paris 2026; submitted for publication), which confirmed its safety in association with D-dimers at the usual cutoff of 500 ng/ml to safely rule out DVT in pregnant patients. However, the diagnostic was quite low as only 7.4% of included patients could have DVT excluded based on this association. When exploring D-dimer at trimester adjusted thresholds of \<500 ng/ml FEUs (1st trimester), \<750 ng/ml FEUs (2nd trimester) and \<1000 ng/ml FEUs (3rd trimester), D-dimer was negative in 142/352 (40.3%) and yielded negative predictive values of 142/142, 100% (95% CI 97.4%-100%). Therefore, we plan a multinational management diagnostic outcome study in pregnant patients with suspected DVT by using 1) an assessment of clinical probability by the LEFt score, 2) trimester-adjusted D-dimer cutoffs, 4) compression ultrasonography.

Conditions

Pregnancy Related; Deep Vein Thrombosis; D-dimer; Diagnostic Strategy

Keywords

Deep vein thrombosis; Pregnancy; D-dimer

Outcome Measures

Primary Outcomes (1)

• • Symptomatic VTE (proximal DVT, PE, or VTE-related death) during 3 months of follow-up in patients with an unlikely LEFt score (0 or 1) and a negative D-dimer who were not treated with anticoagulant therapy during follow-up.

  rate of symptomatic TE events during follow-up

  3 months

Study Arms (1)

D-dimer adapted to prenancy trimester

OTHER

Diagnostic Test: D-dimer

Interventions

D-dimer DIAGNOSTIC_TEST

Pregnant patients with suspected DVT will undergo an assessment of clinical probability, D-dimer adjuste to trimester of pregnany and compression ultrasound.

Also known as: Compression ultrasound

D-dimer adapted to prenancy trimester

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Pregnancy: Confirmed pregnancy (by β-hCG or ultrasound).
• Clinical Suspicion: Presenting with a new onset or worsening of symptoms suggestive of deep vein thrombosis (e.g., leg pain or swelling within the prior month).
• Age: Aged 18 years or older.
• Informed Consent: Ability to provide written informed consent (or emergency consent as per local ethical guidelines).

You may not qualify if:

• Concomitant PE symptoms (chest pain or shortness of breath or syncope/pre-syncope or unexplained tachycardia) except if PE was ruled out by validated methods.
• Current Anticoagulation: Patients already receiving therapeutic doses of anticoagulants (e.g., low-molecular-weight heparin) for more than 48 hours prior to enrolment.
• Other indications for therapeutic anticoagulation
• Previous DVT with suspected ipsilateral recurrence without intervening baseline imaging (baseline imaging defined as CUS done after a minimum of 3 months of treatment for prior proximal DVT).
• Life Expectancy: Presence of a co-morbid condition with a life expectancy of less than 3 months.
• Inaccessibility for Follow-up: Geographical or social factors that would make the mandatory three-month follow-up impossible to complete

Sponsors & Collaborators

• Marc Righini: lead

Study Sites (1)

Righini Marc

Geneva, 1205, Switzerland

Location

MeSH Terms

Conditions

Venous Thrombosis

Condition Hierarchy (Ancestors)

Thrombosis; Embolism and Thrombosis; Vascular Diseases; Cardiovascular Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: No masking
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Dr Med

Model Details: D-dimer dapted to trimester of pregnancy

Study Record Dates

• First Submitted: October 13, 2026
• First Posted: October 21, 2026
• Study Start (Estimated): April 1, 2027
• Primary Completion (Estimated): October 30, 2032
• Study Completion (Estimated): December 1, 2032
• Last Updated: October 21, 2026

Record last verified: 2026-10

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, CSR, ANALYTIC CODE
• Time Frame: 12 months after publication

Locations

CH (1)