From the Guidelines
Thrombophilia is estimated to account for approximately 10-15% of recurrent pregnancy losses, although the exact percentage is not precisely established. Thrombophilias, which are conditions that increase blood clotting tendency, can impair placental blood flow and lead to complications including miscarriage, stillbirth, preeclampsia, and intrauterine growth restriction 1. The most common inherited thrombophilias associated with pregnancy loss include Factor V Leiden mutation, prothrombin gene mutation, protein C and S deficiencies, and antithrombin deficiency. Acquired thrombophilias like antiphospholipid syndrome may account for additional cases.
Key Points to Consider
- Inherited thrombophilias may account for a significant proportion of recurrent pregnancy losses
- The most common inherited thrombophilias associated with pregnancy loss include Factor V Leiden mutation, prothrombin gene mutation, protein C and S deficiencies, and antithrombin deficiency
- Acquired thrombophilias like antiphospholipid syndrome may also contribute to pregnancy loss
- Treatment for women with confirmed thrombophilia and recurrent pregnancy loss typically involves anticoagulation therapy with low molecular weight heparin and sometimes low-dose aspirin
For women with confirmed thrombophilia and recurrent pregnancy loss, treatment typically involves anticoagulation therapy with low molecular weight heparin (such as enoxaparin 40mg daily) and sometimes low-dose aspirin (81mg daily), starting early in pregnancy or even before conception and continuing throughout pregnancy 1. However, not all women with thrombophilia experience pregnancy complications, and routine screening is not recommended for all women with pregnancy loss unless there are other risk factors or multiple losses.
Management of Pregnancy Loss
- Anticoagulation therapy with low molecular weight heparin and sometimes low-dose aspirin may be recommended for women with confirmed thrombophilia and recurrent pregnancy loss
- Routine screening for thrombophilia is not recommended for all women with pregnancy loss unless there are other risk factors or multiple losses
- Management of pregnancy loss should be individualized based on the woman's specific risk factors and medical history.
From the Research
Thrombophilia and Pregnancy Loss
- Thrombophilia, a hypercoagulability disorder, has been associated with pregnancy losses, particularly those occurring after the 12th gestational week 2.
- Studies have shown that inherited or acquired thrombophilia is diagnosed in 50% to 65% of women with a history of unexplained fetal loss 2.
- The prevalence of thrombophilia in women with unexplained recurrent fetal loss (RFL) is significant, with at least one inherited thrombophilic defect found in 36.7% of women with RFL 2.
Percentage of Pregnancy Loss Attributed to Thrombophilia
- While there is no direct percentage stated in the studies, it is noted that thrombophilia is a significant contributor to pregnancy losses, particularly those occurring after the 12th gestational week 2.
- A study found that thrombophilia was present in 54% of women with pregnancy complications, including severe preeclampsia, placental abruption, fetal growth restriction, and unexplained stillbirth 3.
- Another study reported that inherited thrombophilias were found in 13% of women with primary recurrent pregnancy loss (RPL) and 21% of women with secondary RPL 4.
Association Between Thrombophilia and Pregnancy Complications
- Thrombophilia has been linked to various pregnancy complications, including recurrent miscarriage, preeclampsia, placental abruption, and fetal growth restriction 5, 3.
- The presence of antiphospholipid antibodies is a significant contributor to pregnancy losses and other morbidities in pregnant women 5.
- A study found that women with thrombophilia are at increased risk of pregnancy-related venous thromboembolism and other vascular pregnancy complications 5.