VTE Prophylaxis in Pregnancy (Green Top 2015)


Maternal deaths from VTE down from 1.56/100,000 to 0.70/100,000 due to prophylaxis


Which women with prior VTE require thrombophilia testing?


Prior to testing, counsel regarding implications for themselves and family

Test for AT deficiency if: FHx of VTE and either AT def known in family or a specific thrombophilia has not been detected in the family.

Test for APL Antibodies if: the prior VTE was unprovoked


Which women without prior VTE require thrombophilia testing?


Consider testing if: the woman has no personal history or RF’s for VTE but has a FHx of an unprovoked or estrogen-provoked VTE in a 1st degree relative when aged <50.

i.e. if it will change the risk score from 0 to 2.


prophylaxis regimens


Previous VTE Alone (Remember to score any additional factors)

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Thrombophilia Alone (Remember to score any additional factors)

vte 2.png


Risk Scoring for prophylaxis

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A few notes on VTE Treatment in Pregnancy

(see full GTG 2015 guideline for details)



Do not check D-dimer

No role for pre-test probability scores as not validated (ie Wells)


If DVT USS normal but clinical suspicion high, re-scan on days 3 and 7

No need to scan for PE if DVT already proven by USS


VQ higher risk of childhood cancer > CTPA.

CTPA higher risk of maternal breast cancer > VQ.

Absolute risks of both are very small



LMWH dose should be calculated on booking weight

Consider monitor Anti-Xa if weight <50kg or >90kg

Continue through pregnancy and for 6 weeks postpartum, or for three months – whichever is the longer duration



If VTE occurs at term, consider UFH infusion

Stop LMWH at start of labour, or 24 hours prior to a planned delivery,

Neuroaxial anaesthetic should not be performed until 24 hours after last dose of LMWH, and next dose should not be given until 4 hours after the procedure. The catheter should not be removed within 12 hours after the last dose.