Role of Thrombophilia in Adverse Obstetric Outcomes and Their Prevention Using Antithrombotic Therapy

ABSTRACT

A series of case-control studies in the last decade have shown the role of inherited thrombophilia in the occurrence of adverse obstetric outcomes. In small series of cases, it has been proven that rare inherited causes of thrombophilia such as natural anticoagulant deficiencies can be associated with fetal losses. The confirmed presence of antiphospholipid antibodies in plasma, representing an acquired thrombophilic condition, is also an established cause of fetal losses, although other studies with a smaller sample size have found an association with other obstetric complications, namely preeclampsia, fetal growth restriction, and abruption placentae. Case-control studies have been performed regarding the potential association between unexplained fetal losses and mild hyperhomocysteinemia. Although case-control and prospective studies are also available regarding hyperhomocysteinemia and other gestational vascular complications, published data are conflicting. Intervention studies have been performed to prevent adverse obstetric outcomes in women with inherited or acquired thrombophilia and previous adverse outcomes. There is much debate in the literature regarding the need for treatment of women with thrombophilia during pregnancy. Although in most cases these are not randomized controlled trials, all studies found significantly better outcomes in treated pregnancies compared with those of untreated pregnancies.

KEYWORDS

Thrombophilia - adverse pregnancy outcomes - prophylaxis

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