ABSTRACT
There has been an sudden increase of knowledge about thrombophilias in the last decade
as new thrombophilias are discovered and new associations are explored. It is now
evident that thrombophilias are common and that the clinical consequences of having
a thrombophilia do not appear to be limited to venous thromboembolism. The placenta-mediated
pregnancy complications are also common (more than one in six pregnancies are affected)
and include pregnancy loss, preeclampsia, placental abruption, and intrauterine growth
restriction. These complications as a whole are the leading causes of maternal and
neonatal morbidity in the developed world. Evidence has emerged to suggest that thrombophilic
women may be at higher risk of developing these placenta-mediated pregnancy complications.
However, is this evidence mature enough to claim that a causal association is proven?
Is the evidence strong enough to recommend anticoagulant prophylaxis? We suggest that
causality is not yet proven and that the data to support management with anticoagulant
prophylaxis in thrombophilic pregnancies is too immature to consider this an established
intervention.
KEYWORDS
Thrombophilia - intrauterine growth restriction (IUGR) - preeclampsia - pregnancy
loss - placental abruption
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Dr. Marc A Rodger
Division of Hematology, The Ottawa Hospital, General Campus
501 Smyth Rd., Ottawa, Ontario, Canada K1H 8L6
Email: mrodger@ohri.ca