Anticoagulation Regimens in Pregnancy
| Type of Anticoagulation | Dosing Regimen |
|---|
| Prophylactic | LMWH | Enoxaparin 40 mg SC every 24 h Dalteparin 5000 U SC every 24 h Tinzaparin 4500 U SC every 24 h or 75 U/kg SC every 24 h
| | UFH | UFH 5000 U SC every 12 h | | Alternative | UFH 5000-7500 U SC every 12 h in first trimester UFH 7500-10 000 U SC every 12 h in second trimester UFH 10 000 U SC every 12 h in third trimester (unless aPTT elevated)
| | Intermediate dose | LMWH | | | Therapeutic/treatment (weight-adjusted) dose | LMWH | Enoxaparin 1 mg/kg SC every 12 h Dalteparin 200 U/kg SC every 24 h or 100 U/kg SC every 12 h Tinzaparin 175 U/kg SC every 24 h
| | UFH | UFH 10 000 U or more SC every 12 h; doses adjusted to obtain midinterval (6 h postinjection) therapeutic aPTT (often a ratio of 1.5-2.5) | | Postpartum anticoagulation (for 4-6 wk) | Warfarin | Adjust dose to target INR of 2.0 – 3.0 with initial UFH or LMWH overlap until INR is > 2.0 for 2 days | | LMWH or UFH | Prophylactic, intermediate, or therapeutic dose |
|
Abbreviations: aPTT, activated partial thromboplastin time; INR, international normalized ratio; LMWH, low-molecular-weight heparin; SC, subcutaneously; UFH, unfractionated heparin.
aAdapted from BatesSM, MiddeldorpS, RodgerM, JamesAH, GreerI. Guidance for the treatment and prevention of obstetric-associated venous thromboembolism. J Thromb Thrombolysis. 2016;41:92-128 and American College of Obstetricians and Gynecologists Committee on Practice Bulletins—Obstetrics. ACOG Practice Bulletin No. 196: thromboembolism in pregnancy. Obstet Gynecol. 2018;132:e1-e17.
bPostpartum anticoagulation should be greater or equal to antepartum therapy.