What is the use of Clexane (enoxaparin) in pregnant women?

From the Guidelines

Clexane (enoxaparin) is the preferred low molecular weight heparin (LMWH) for use in pregnant women when anticoagulation is needed, due to its safety and efficacy profile, as supported by the American College of Chest Physicians evidence-based clinical practice guidelines 1.

Key Considerations

• The typical prophylactic dose of Clexane ranges from 40mg once daily to 40mg twice daily, while therapeutic dosing is weight-based at approximately 1mg/kg twice daily.
• Dosage adjustments may be needed as pregnancy progresses due to weight changes and increased blood volume.
• Treatment should be monitored with anti-Factor Xa levels in certain cases, especially with therapeutic dosing.
• Common indications include prevention or treatment of venous thromboembolism, management of thrombophilias, and prevention of pregnancy complications in women with antiphospholipid syndrome.

Administration and Monitoring

• Clexane is typically administered as a subcutaneous injection in the abdominal area, avoiding the 2cm area around the umbilicus.
• Viscoelastic testing, such as TEG, can be used to detect the anticoagulant effect of Clexane, with a study suggesting that 40mg of enoxaparin has a greater anticoagulant effect than 7500 IU of unfractionated heparin 1.

Special Considerations

• When delivery approaches, Clexane is usually discontinued 24 hours before planned induction or cesarean section to reduce bleeding risk, and resumed 6-12 hours after delivery if continued anticoagulation is needed.
• Side effects may include injection site bruising, minor bleeding, and rarely, allergic reactions.

Guideline Recommendations

• The American College of Chest Physicians recommends low-molecular-weight heparin, such as Clexane, for the prevention and treatment of VTE in pregnant women instead of unfractionated heparin (Grade 1B) 1.
• For pregnant women with acute VTE, anticoagulants should be continued for at least 6 weeks postpartum (for a minimum duration of therapy of 3 months) compared with shorter durations of treatment (Grade 2C) 1.

From the Research

Use of Clexane (Enoxaparin) in Pregnant Women

• Clexane (enoxaparin) is used in pregnant women for thromboprophylaxis, particularly in those at high risk of thromboembolism 2, 3, 4.
• The main indications for enoxaparin use in pregnancy include:
  • Prophylaxis of venous thromboembolism 3, 4
  • Prevention of pregnancy loss in thrombophilic women 3
  • Treatment of venous thromboembolism 3, 5, 4
  • Prophylaxis of arterial thrombosis in pregnant women with mechanical heart valves 3
  • Prevention of late gestational complications such as pre-eclampsia and intrauterine growth restriction 3
• Enoxaparin does not cross the placenta and is safe for the fetus 3.
• Maternal side effects are uncommon and include:
  • Mild localized allergic reactions (2%) 3
  • Increased bleeding (2%), which is dose-dependent 3
  • Heparin-induced thrombocytopenia (very rare) 3, 4
  • Bone resorption (not clinically relevant) 3
• The recommended dose of enoxaparin in pregnancy is usually 40 mg, subcutaneously daily 2, 4.
• Enoxaparin has been shown to be effective in preventing venous thromboembolism in pregnant women, with a low incidence of complications 2, 3, 4.