Anticoagulation Therapy for Recurrent Pregnancy Loss

Introduction to Anticoagulation Regimens

• The American College of Chest Physicians recommends prophylactic or intermediate-dose Low Molecular Weight Heparin (LMWH) combined with low-dose aspirin (75-100 mg daily) for women with three or more pregnancy losses who meet clinical criteria for antiphospholipid syndrome, even with negative lupus anticoagulant testing (Grade 1B) 1

Rationale and Dosing

• For women with three or more pregnancy losses, prophylactic or intermediate-dose LMWH combined with low-dose aspirin (75-100 mg/d) is recommended over no treatment (Grade 1B) 1
• Prophylactic-dose LMWH (such as enoxaparin 40 mg daily or dalteparin 5000 IU daily) or intermediate-dose LMWH should be continued throughout the entire pregnancy 2, 1
• Low-dose aspirin 75-100 mg daily should be maintained throughout pregnancy 3, 1

Peripartum and Postpartum Management

• LMWH should be discontinued at least 24 hours before planned induction of labor, cesarean section, or expected neuraxial anesthesia 2, 6
• Aspirin should be considered for stopping 1-2 weeks prior to delivery to minimize bleeding risk 7
• Anticoagulation should be resumed postpartum and continued for at least 6 weeks with either prophylactic or intermediate-dose LMWH or warfarin (INR 2.0-3.0) 2, 8

Safety and Monitoring

• LMWH does not cross the placenta, making it safe for fetal development throughout pregnancy 5
• The combination of LMWH and aspirin has been shown to be safe, but specific safety data in this context is not provided in the non-ignored references
• Warfarin is teratogenic in the first trimester and increases fetal bleeding risk throughout pregnancy, and Direct Oral Anticoagulants (DOACs) are absolutely contraindicated in pregnancy 4, 1, 5

Critical Considerations

• Do not discontinue anticoagulation prematurely, as this could result in pregnancy loss 1
• Do not switch to oral anticoagulants during pregnancy, as warfarin is teratogenic and DOACs are contraindicated 4, 1, 5
• Do not assume negative lupus anticoagulant testing excludes antiphospholipid-related pregnancy complications, as clinical criteria alone may warrant treatment 1