Thrombophilias in Pregnancy
Adham S. Abu Taha, PhD
Division of Pharmacology, College of Human Medicine and Health Sciences
An-Najah National University, Nablus, Palestine
Several changes take place in the haemostatic system during pregnancy and act as a physiological “safety net” for the peripartum period, but can predispose both the mother and fetus to complications during the pregnancy. These changes include: a significant increase in clotting factors, a marked decrease in anticoagulant activity and reduced fibrinolytic activity.
These complications include both early (recurrent miscarriage) and late placental vascular-mediated problems (fetal loss, pre-eclampsia, placental abruption and intra-uterine growth restriction). The risks are inherently higher in women with acquired or inherited thrombophilia, but at present routine screening for these disorders are not routinely recommended in the absence of venous thromboembolism.
Low dose aspirin and low molecular weight heparin (LMWH) have proven their effectiveness in increasing live birth rates in the setting of antiphospholipid syndrome. However, their use in the context of inherited thrombophilia and pregnancy complications is less well established. There is however increasing evidence for the use of heparin in women with pregnancy complications mediated by the placenta, selected by previous pregnancy outcome and not by thrombophilic defect. Due to their excellent safety record, these treatments have been offered to women at high risk of adverse pregnancy outcome in advance of the scientific evidence becoming available for their use.