Anticoagulation in Pregnancy

Primary Recommendation: LMWH as First-Line Therapy

The American College of Chest Physicians recommends low-molecular-weight heparin (LMWH) as the preferred agent for both prevention and treatment of venous thromboembolism throughout pregnancy, due to its superior pharmacokinetic profile and better safety profile compared to unfractionated heparin (UFH) 1, 2
LMWH should be used instead of UFH for all pregnant patients requiring anticoagulation for VTE prevention or treatment, based on its longer half-life allowing less frequent dosing 1, 2

For pregnant women with acute VTE, initiate LMWH immediately and continue throughout pregnancy, with a strong recommendation based on LMWH's superior pharmacokinetic profile and better safety profile 1, 2
Extend anticoagulation for at least 6 weeks postpartum, with a minimum total treatment duration of 3 months, as recommended by the American College of Chest Physicians 1, 3

The American College of Chest Physicians recommends against the use of oral direct thrombin inhibitors (dabigatran) during pregnancy, with a Grade 1C recommendation 3
The American College of Chest Physicians recommends against the use of oral factor Xa inhibitors (rivaroxaban, apixaban) during pregnancy, with a Grade 1C recommendation 3
The American College of Chest Physicians recommends against the use of vitamin K antagonists (warfarin) during the first trimester, with a Grade 1A recommendation to use LMWH instead, due to risk of embryopathy and early miscarriage 2, 3

For proven acute superficial vein thrombosis in pregnancy, use LMWH rather than no anticoagulation, as recommended by the American Society of Hematology 1
For hemodynamically stable PE with right ventricular dysfunction, use anticoagulation alone without adding systemic thrombolysis, as recommended by the American College of Chest Physicians 1
For life-threatening hemodynamically unstable PE, add systemic thrombolytic therapy to anticoagulation, as recommended by the American College of Chest Physicians 1

The American College of Chest Physicians recommends that UFH, LMWH, warfarin, acenocoumarol, and danaparoid are safe for breastfeeding women, with Grade 1A or 1B recommendations 1, 2, 3, 4
The American College of Chest Physicians recommends against the use of oral direct thrombin and factor Xa inhibitors during breastfeeding, with a Grade 2C recommendation 2, 3