The Use of a Scoring System to Guide Thromboprophylaxis in a High-Risk Pregnant Population
Anticoagulation recommendations published in the BJOG, August 1999 .
Very high risk
Previous VTE while taking anticoagulants
Thromboprophylaxis with dose adjusted for anti-Xa activity throughout pregnancy and for 12 weeks postpartum.
VTE in the current pregnancy
Previous VTE while not on anticoagulants
Fixed dose of LMWH from 24 weeks, earlier if additional risk factors for VTE. With previous pregnancy associated VTE, start 4–6 weeks ahead of gestation of the previous event and continue for 12 weeks postpartum.
Protein C deficiency and FMH
Homozygous Factor V Leiden
Homozygous prothrombin gene mutation
Heterozygous factor V Leiden
Postpartum LMWH prophylaxis for 6 weeks.
Heterozygous prothrombin gene mutation
Heterozygous protein S deficiency
Relatively low risk
Heterozygous Factor V Leiden with no FMH
Monitor for additional risks.
Heterozygous PT gene mutation with no FMH
VTE: venous thromboembolism, LMWH: low molecular weight heparin, FMH: family history of VTE.