Short course of low‑dose heparin to prevent postpartum blood clots

Short-term Low-dose Low-molecular-weight Heparin to Prevent Postpartum Thrombosis: a Pragmatic, Multi-center, Open-label Randomized Controlled Study

This study will test whether a short 7–10 day course of low‑dose low‑molecular‑weight heparin after delivery reduces blood clots and how it affects bleeding and wound problems in postpartum women with certain risk factors.

Quick facts

• Phase: PHASE3
• Study type: Interventional
• Enrollment: 9200 (estimated)
• Ages: 18 Years and up
• Sex: Female
• Sponsor: University Hospital, Geneva (other)
• Locations: 1 site (Geneva)
• Trial ID: NCT07140211 on ClinicalTrials.gov

What this trial studies

This phase 3 interventional study compares a short 7–10 day course of low‑dose low‑molecular‑weight heparin (LMWH) to no anticoagulation in postpartum women who meet specified risk-factor thresholds. Participants will receive LMWH or no treatment and be followed for 90 days after delivery to capture symptomatic venous thromboembolism, bleeding events, and wound complications. Women requiring therapeutic anticoagulation, judged high risk for postpartum VTE, with increased bleeding risk, or with contraindications to heparin are excluded. The primary outcomes are VTE within 90 days and the balance of bleeding and wound complications between arms.

Who should consider this trial

Good fit: Postpartum women after delivery who have at least one major risk factor or two minor risk factors for VTE and no contraindication to heparin.

Not a fit: Women who already need full therapeutic anticoagulation, are considered high risk for postpartum VTE, have an increased bleeding risk, or cannot receive heparin are unlikely to benefit from this low‑dose short regimen.

Why it matters

Potential benefit: If successful, this approach could lower postpartum blood clots while limiting anticoagulant exposure to a short 7–10 day course.

How similar studies have performed: Full‑dose anticoagulation has shown benefit in high‑risk postpartum patients, but the specific use of short‑term low‑dose LMWH in this moderate‑risk postpartum population has limited prior evidence.

Eligibility criteria

Inclusion Criteria: postpartum women after delivery AND ≥1 major risk factor / ≥2 minor risk factors:

* Major risk factors: Emergency cesarean section ; Pre-pregnancy BMI ≥35kg/m2 ; Known low-risk thrombophilia (heterozygous factor V Leiden; heterozygous G20210 prothrombin mutation) ; Pre-eclampsia ; Pre-term delivery ; Peripartum systemic infection ; Intra-uterine growth restriction ; Pregnancy loss
* Minor risk factors: Age ≥35 years ; Pre-pregnancy BMI 30.0-34.9kg/m2 ; Current smoking ; Elective cesarean section ; Postpartum hemorrhage ; Antenatal immobility

Exclusion Criteria:

* ≥2 doses of postpartum LMWH
* Any indication for therapeutic anticoagulation
* A high-risk of postpartum VTE
* An increased bleeding risk
* A contra-indication to heparin

Where this trial is running

Geneva

• Geneva University Hospitals — Geneva, Switzerland (RECRUITING)

Study contacts

• Study coordinator: Marc Blondon

Conditions: Venous Thromboembolism, Postpartum