From the Guidelines
The treatment for deep vein thrombosis (DVT) during pregnancy primarily involves low molecular weight heparin (LMWH) such as enoxaparin (Lovenox) or dalteparin (Fragmin), which is the preferred anticoagulant due to its safety profile. Typical dosing is enoxaparin 1 mg/kg twice daily or dalteparin 100 IU/kg twice daily, with adjustments based on weight and renal function 1. Treatment should continue throughout pregnancy and for at least 6 weeks postpartum, with a minimum total duration of 3 months 1. Unfractionated heparin may be used in certain situations, particularly around delivery time. Warfarin and direct oral anticoagulants (DOACs) are contraindicated during pregnancy due to their ability to cross the placenta and potential teratogenic effects 1.
Some key considerations for the management of DVT in pregnancy include:
- Regular monitoring through anti-Xa levels is recommended, especially as blood volume changes during pregnancy 1
- Physical measures like compression stockings can help manage symptoms and reduce swelling
- Treatment should be temporarily discontinued 24 hours before planned delivery or immediately if spontaneous labor begins, and resumed 12-24 hours after delivery if no significant bleeding occurs
- Antepartum prophylaxis is suggested for pregnant women at increased risk, such as those with previous unprovoked VTE, pregnancy or estrogen-related VTE, homozygous factor V Leiden or prothrombin G20210A, or antiphospholipid antibody syndrome 1
The use of LMWH is supported by guidelines from the American College of Chest Physicians, which recommend LMWH over unfractionated heparin for the prevention and treatment of VTE in pregnant women 1. Overall, the goal of treatment is to effectively manage the clot while protecting both mother and fetus, as heparins do not cross the placenta and therefore don't affect fetal development or increase bleeding risk in the baby.
From the Research
Treatment for Deep Vein Thrombosis (DVT) in Pregnancy
- The treatment of DVT during pregnancy typically involves the use of low-molecular-weight heparin (LMWH) as the preferred therapy 2, 3, 4, 5, 6.
- LMWH is used because it has been shown to successfully treat DVT with few significant side effects 2.
- The dosage of LMWH may vary, with some studies suggesting a single daily dose of 1.5 mg/kg enoxaparin is as effective as twice-daily administration 2.
- Treatment with LMWH should continue throughout pregnancy and for at least six weeks postpartum, for a total minimum duration of therapy of six months 3, 5.
- In some cases, anticoagulation therapy may need to be interrupted near term to allow for delivery, and placement of a retrievable inferior vena cava filter may be considered 4.
- Warfarin may be given as adjuvant therapy along with LMWH in the post-partum period, and LMWH can be discontinued when an international normalized ratio of 2 or above is reached 2.
- Thromboprophylaxis using LMWH during pregnancy is essential, especially in women at high risk of thromboembolism, and the dosage should be adjusted according to individual risk assessment 6.
Anticoagulation Management
- The decision about anticoagulant management during pregnancy should include an assessment of additional risk factors for thromboembolism, including valve type, position, and history of thromboembolism 5.
- For women with mechanical heart valves, adjusted-dose bid LMWH or adjusted-dose UFH throughout pregnancy may be recommended, or one of these two regimens until the thirteenth week with warfarin substitution until close to delivery before restarting LMWH or UFH 5.
- For women with a history of VTE, antepartum prophylactic or intermediate-dose LMWH or UFH, followed by postpartum anticoagulants, may be recommended 5.