Postpartum aspirin to prevent blood clots after delivery

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

The PARTUM trial is a non-inferiority, PROBE design comparing low-dose aspirin to low-molecular-weight heparin for 42 days after delivery in individuals with VTE risk factors. Participants are identified during pregnancy and up to 48 hours postpartum and randomized to aspirin or LMWH, with follow-up at 6 weeks and 90 days. The study uses site-specific LMWH regimens and aspirin dosing by country availability. Outcomes focus on thromboembolic events, safety, and feasibility of a non-inferiority approach in postpartum care.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* ONE (or more) First Order Criterion:

  1. Known inherited thrombophilia diagnosed prior to enrolment, regardless of family history of VTE:

     i. Heterozygous factor V Leiden, or ii. Heterozygous prothrombin gene variant, or iii. Protein C deficiency, or iv. Protein S deficiency, and/or
  2. Antepartum immobilization for ≥7 days. Immobilization is defined as bed rest with 90% of waking hours spent in bed at any time during the antepartum period AND/OR

TWO (or more) Second Order Criteria:

1. Pre-pregnancy BMI ≥30 kg/m²
2. Smoking in the current pregnancy or within 3 months prior to pregnancy
3. Previous clinical history of superficial vein thrombosis
4. Preeclampsia
5. Current pregnancy ending in stillbirth (pregnancy loss \>20 weeks gestation)
6. Unplanned cesarean delivery (unplanned = not a scheduled cesarean delivery)
7. Small-for-gestational-age infant at time of delivery (\<3rd percentile adjusted for gestational age and sex)
8. Peripartum or postpartum infection (symptoms/signs of infection and documented fever and laboratory evidence of infection with positive blood cultures or an elevated white blood cell count based on local laboratory cutoffs)
9. Postpartum hemorrhage (≥1000 mL of blood loss, regardless of delivery mode)

Exclusion Criteria:

1. More than 48 hours since delivery at the time of randomization
2. Received more than 1 dose of LMWH since delivery
3. Need for postpartum LMWH prophylaxis or systemic anticoagulation as judged by their physician and/or local investigator. May include but is not limited to:

   1. Documented history of provoked or unprovoked VTE
   2. Mechanical heart valve(s)
   3. Known antiphospholipid syndrome (APS)
   4. Known high-risk inherited thrombophilia i) Antithrombin deficiency, or ii) Homozygous factor V Leiden, or iii) Homozygous prothrombin gene mutation, or iv) More than 1 thrombophilia: any combination of 2 or more: factor V Leiden, prothrombin gene mutation, protein C deficiency, protein S deficiency
4. Need for postpartum ASA as judged by their physician and/or local investigator. May include but is not limited to:

   1. Documented history of myocardial infarction
   2. Documented history of ischemic stroke or transient ischemic attack (TIA)
5. Active bleeding, excluding normal vaginal bleeding, at the time of randomization
6. Known medical condition as judged by their physician and/or local investigator to be a contraindication to ASA or LMWH including known ASA or LMWH allergy
7. \<18 years of age
8. Unable or declined consent

Where it's running

• Foothills Medical Centre
  Calgary, Alberta, Canada Recruiting
• Association Hospitalière De Bruxelles Et De Schaerbeek - Centre Hospitalier Universitaire Brugmann
  Brussels, Belgium Not yet recruiting
• The Ottawa Hospital - General Campus
  Ottawa, Ontario, Canada Not yet recruiting
• Hvidovre Hospital
  Hvidovre, Capital Region, Denmark Not yet recruiting
• CHU de Nancy
  Nancy, France Not yet recruiting
• APHP - Hôpital Port Royal
  Paris, France Not yet recruiting

Study contacts

• Principal investigator: Leslie Skeith, MD — University of Calgary
• Study coordinator: Leslie Skeith, MD
• Email: laskeith@ucalgary.ca
• Phone: 403-944-5246

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.