Doses (according to RCOG 2009 and SEGO 2012)
Prophylactic dose of LMWH
Intermediate dose of LMWH
Therapeutic dose LMWH, UFH and Fondaparinux
| < 50 kg | 50-90 kg | 91-130 kg | 131-170 kg | > 170 kg | |
|---|---|---|---|---|---|
| Enoxaparin | 20 mg/24 h | 40 mg/24 h | 60 mg/24 h | 80 mg/24 h | 0,6 mg/kg/24 h |
| Tinzaparin | 3500 UI/24 h | 4500 UI/24 h | 7000 UI/24 h | 9000 UI/24 h | 75 UI/kg/24 h |
| Bemiparin | 2500 UI/24 h | 3500 UI/24 h | 5000 UI/24 h | 7500 UI/24 h | 75 UI/kg/24 h |
| Dalteparin | 2500 UI/24 h | 5000 UI/24 h | 7500 UI/24 h | 10000 UI/24 h | 75 UI/kg/24 h |
| Weight between 50 to 90 kg | |
|---|---|
| Enoxaparin | 40 mg/12 h or 60 mg/24 h |
| Dalteparin | 5000 UI/12 h |
| Authors’ note: Bemiparin and tinzaparin: They do not include dosages every 12 h in their technical data sheets. | |
| Adapted to weight | |
|---|---|
| Enoxaparin | 1 mg/kg/12 h or 1,5 mgr/Kg/24h ANTENATAL and POSTNATAL |
| Tinzaparin | 175 UI/kg/24 h ANTENATAL and POSTNATAL |
| Bemiparin | 115 UI/kg/24 h ANTENATAL and POSTNATAL |
| Dalteparin | 100 UI/kg/12 h or 200 UI/kg/24 h ANTENATAL and POSTNATAL |
| Non-fractionated heparin | 5000 UI (80 UI/Kg weight) followed by continuous iv perfusion 18 IU/kg (APTT 1.5-2.5) |
| Fondaparinux | 5 mg/d (< 50Kg) 7.5 mg/d (50-100 Kg) 10 mg/d (> 100 Kg) |
| Authors’ note: During the weeks closest to the birth, fractionating the dose of heparin every 12 hours is recommended in order to facilitate management of anaesthetic techniques. | |
Control of expectant mother with LMWH
1. Prophylactic and Intermediate doses of LMWH:
-
Anti-Xa level does not need to be monitored, except in patients with impaired renal function and extreme weights.
-
Does not require platelet control, unless prior exposure to non-fractionated heparin.
Therapeutic doses of LMWH:
-
Anti-Xa control not routinely, recommendable 4 hours after administering the dose of heparin, monthly control. Obtain values of 05.-1 U/mL.
-
Platelet control during first 10 to 15 days before onset of treatment.
RCOG Green-top Guideline nº37 nov 2009;1-35.
Administration
LMWH is administered subcutaneously
Contraindications for LMWH
| Active antenatal and post-partum bleeding. |
| Woman considered to have high risk of bleeding (for example, placenta praevia). |
| Woman with coagulation impairment (von Willebrand disease, haemophilia or acquired coagulopathy). |
| Thrombocytopenia (<75,000 mm3). |
| Renal disease (FG < 30 mL/min/1.73 m2 |
| Severe liver disease (prolonged TP or PHT with oesophageal varices). |
| Uncontrolled hypertension (SBP > 200 mmHg or DBP > 120 mmHg). |
| Past history of cerebrovascular accident (ischaemic or haemorrhagic) in the last 4 weeks. |
Safety
Safety of Anticoagulants in Pregnancy and Breastfeeding
FDA Classification according to risk in pregnancy
FDA Classification according to risk in breastfeeding
| Drugs | Category | Pregnancy (FDA) | Breastfeeding | |
|---|---|---|---|---|
| FDA | Hospital of Denia http://www.e-lactancia.org/ |
|||
| Acenocoumarol | Anticoagulant | X | N | Safe, there is no risk for infant |
| Acetylsalicylic | AINE | C/D | N | Quite safe, mild risk not very lukely |
| Antithrombin | Antithrombotic | B | ND | (there is no info) |
| Bemiparin | Anticoagulant | C | ND | Safe, there is no risk for infant |
| Clopidogrel | Antiplatelet | B | ND | Unsafe: risk |
| Dabigatran | Anticoagulant | X | ND | Unsafe: risk |
| Dalteparin | Anticoagulant | B | Y | Safe, there is no risk for infant |
| Enoxaparin | Anticoagulant | B | Y | Safe, there is no risk for infant |
| Fondaparinux | Anticoagulant | B | ND | Safe, there is no risk for infant |
| Heparin | Anticoagulant | C | Y | Safe, there is no risk for infant |
| Nadroparin | Anticoagulant | B | ND | Safe, there is no risk for infant |
| Protamine | Heparin antidote | C | ND | Quite safe, mild risk not very likely |
| Rivaroxaban | Anticoagulant | X | N | (there is no info) |
| Tinzaparin | Anticoagulant | B | ND | Safe, there is no risk for infant |
| Tranexamic, acid | Antifibrinolytic | B | Y | Safe, there is no risk for infant |
| Triflusal | Antiplatelet | ND | ND | (there is no info) |
| Warfarin | Anticoagulant | X | Y | Safe, there is no risk for infant |
| Category A | No apparent risk. No evidence of risk to the foetus. THEY CAN BE USED. |
| Category B | No apparent risks. There are no studies of risk in human. PROBABLY SAFE. |
| Category C | No existence of risk cannot be ruled out. There are no studies of risk in human. Risk has been shown in animals and studies have faile to demonstrate its innocuousness. They can only be used when potential benefits warrant risks to the foetus. AVOID THEM IF THERE ARE OTHER ALTERNATIVES. |
| Category D | Moderate risk. There is evidence of risk. Potential benefits in pregnant women may outweigh the risk of its use, such as life-threatening situations for women or serious illness AVOID THEM IF THERE ARE OTHER ALTERNATIVES. |
| Category E | There is evidence of foetal risk in humans. The risk outweighs any benefit of the use of the drug. CONTRAINDICATED |
| Y | Yes, it can be administered. |
| N | It must not be administered. The use of the drug is not recommendable or breastfeeding must be interrupted during its administration. |
| ND | No documented information is available. |
LMWH Informed Consent
Adverse Reactions
Haemorrhages.
Liver test alteration.
Severe skin allergy or heparin-induced thrombocytopenia (HIT).
We suggest using Fondaparinux and direct thrombin inhibitors for pregnant women with severe skin allergy or heparin-induced thrombocytopenia. (Grade 2C CHEST 2012).
Osteoporosis and spontaneous fractures.
The risk of osteoporosis related to the use of LMWH is very low so no calcium supplements are required during treatment (RCOG 2009).