Drugs

Doses (according to RCOG 2009 and SEGO 2012)
Prophylactic dose of LMWH
 < 50 kg50-90 kg91-130 kg131-170 kg> 170 kg
Enoxaparin20 mg/24 h40 mg/24 h60 mg/24 h80 mg/24 h0,6 mg/kg/24 h
Tinzaparin2500 UI/24 h4500 UI/24 h7000 UI/24 h9000 UI/24 h75 UI/kg/24 h
Bemiparin2500 UI/24 h3500 UI/24 h5000 UI/24 h7500 UI/24 h75 UI/kg/24 h
Dalteparin2500 UI/24 h5000 UI/24 h7500 UI/24 h10000 UI/24 h75 UI/kg/24 h
Intermediate dose of LMWH
Weight between 50 to 90 kg
Enoxaparin40 mg/12 h or 60 mg/24 h
Dalteparin5000 UI/12 h
Authors’ note: Bemiparin and tinzaparin: They do not include dosages every 12 h in their technical data sheets.
Therapeutic dose LMWH, UFH and Fondaparinux
Adapted to weight
Enoxaparin1 mg/kg/12 h or 1,5 mgr/Kg/24h ANTENATAL and POSTNATAL
Tinzaparin175 UI/kg/24 h ANTENATAL and POSTNATAL
Bemiparin115 UI/kg/24 h ANTENATAL and POSTNATAL
Dalteparin100 UI/kg/12 h or 200 UI/kg/24 h ANTENATAL and POSTNATAL
Non-fractionated heparin5000 UI (80 UI/Kg peso) seguido de 1000-2000 UI/Kg/h.(control r-TTPa 1.5-2.5)
Fondaparinux5 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.
  • Does not require platelet control, unless prior exposure to non-fractionated heparin.
Therapeutic doses of LMWH:
  • Anti-Xa control recommendable 5 to 6 hours after administering the dose of heparin, monthly control. Obtain values of 0.4-1.2 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.
RCOG Green-top Guideline nº37 nov 2009;1-35. SEGO 2012.
Safety
Safety of Anticoagulants in Pregnancy and Breastfeeding
DrugsCategoryPregnancy
(FDA)
Breastfeeding
FDAHospital of Denia
http://www.e-lactancia.org/
AcenocoumarolAnticoagulantXNSafe, there is no risk for infant
AcetylsalicylicAINEC/DNQuite safe, mild risk not very lukely
AntithrombinAntithromboticBND(there is no info)
BemiparinAnticoagulantCNDSafe, there is no risk for infant
ClopidogrelAntiplateletBNDUnsafe: risk
DabigatranAnticoagulantXNDUnsafe: risk
DalteparinAnticoagulantBYSafe, there is no risk for infant
EnoxaparinAnticoagulantBYSafe, there is no risk for infant
FondaparinuxAnticoagulantBNDSafe, there is no risk for infant
HeparinAnticoagulantCYSafe, there is no risk for infant
NadroparinAnticoagulantBNDSafe, there is no risk for infant
ProtamineHeparin antidoteCNDQuite safe, mild risk not very likely
RivaroxabanAnticoagulantXN(there is no info)
TinzaparinAnticoagulantBNDSafe, there is no risk for infant
Tranexamic, acidAntifibrinolyticBYSafe, there is no risk for infant
TriflusalAntiplateletNDND(there is no info)
WarfarinAnticoagulantXYSafe, there is no risk for infant
FDA Classification according to risk in pregnancy
Category ANo apparent risk. No evidence of risk to the foetus. THEY CAN BE USED.
Category BNo apparent risks. There are no studies of risk in human. PROBABLY SAFE.
Category CNo 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 DModerate 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 EThere is evidence of foetal risk in humans. The risk outweighs any benefit of the use of the drug. CONTRAINDICATED
FDA Classification according to risk in breastfeeding
YYes, it can be administered.
NIt must not be administered. The use of the drug is not recommendable or breastfeeding must be interrupted during its administration.
NDNo documented information is available.
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).