Thrombophilia in Pregnancy
Some women in pregnancy are predisposed to thrombosis through genetic or acquired changes in their coagulation or fibrinolytic system. Many patients are usually asymptomatic to begin with and manifest symptoms for the first time during pregnancy. The most common manifestation of thrombophilia in pregnancy is maternal venous thromboembolism. They can also have transient-ischemic attackes, stroke, superficial thrombophlebitis, and fetal loss. Maternal risk of complications is high. However, unique risks to the fetus have not been consistently demonstrated. Screening for thrombophilia is not appropriate on the grounds of recurrent fetal loss, placental abruption, fetal growth restriction or pre-eclampsia.
Classification of thrombophilias
| Classification | Thrombophilias |
|---|---|
| High-risk inherited | Factor V leiden mutation (homozygous), Prothrombin G20210A mutation (homozygous), Antithrombin III deficiency |
| Low-risk inherited thrombophilias | Factor V leiden mutation (heterozygous), Prothrombin G20210A mutation (heterozygous), Protein S and Protein C deficiency |
| Acquired thrombophilia | Antiphospholipic antibody syndrome |
Common causes of thrombophilia in pregnancy
| Cause | Description |
|---|---|
| Factor V Leiden mutation | Most common cause of thrombophilia |
| Antiphospholipis syndrome (APS) | Most common cause of acquired thrombophilia, probably due to a ‘second-hit’ mechanism. Lupus anticoagulant (LA), anticardiolipin (aCL) and anti-beta-2-glycoprotein antibodies increased the risk for thrombosis and increase vascular tone. It may be associated with systemic lupus erythematosus (SLE). . It is associated with thrombosis, recurrent miscarriage, early onset pre-eclampsia, early onset fetal growth restriction, stillbirth, livedor reticularis, stroke, and superficial thrombophlebitis. |
| Others | Deficiency of protein C, protein S and Antithrombin III, prothrombin mutation G20210A |
- Indications for screening for thrombophilia
- Personal history of idiopathic or recurrent DVT/VTE
- Family history of DVT/VTE in a first-degree relative (especially if < 50 years old)
- Investigations
- Factor V Leiden mutation
- Prothrombin G20210A mutation (PGM)
- Antiphospholipid syndrome
- Deficiency of protein C, protein S, and antithrombin III
- Hyperhomocysteinemia
