Low-molecular-weight heparin for the prevention and treatment of venous thromboembolism in pregnancy.

Abstract

Low-molecular-weight heparins (LMWHs) have largely replaced unfractionated heparins for both prophylaxis and treatment of venous thromboembolism in nonpregnant patients. However, until recently, evidence in pregnant women was lacking, despite the increasing use of LMWHs during pregnancy in clinical practice. This review covers recent literature on the use of LMWHs in relation to pregnancy. The main areas covered in this review are the use of LMWHs in both prophylaxis and treatment of venous thromboembolism in pregnancy. The review also considers issues relating to monitoring of LMWHs in pregnancy, and safety from both a maternal and a fetal perspective. The available evidence demonstrates that LMWHs are of at least equivalent efficacy but have a better safety profile compared with unfractionated heparins in both prophylaxis and treatment of maternal venous thromboembolism, and are more convenient to administer. There is no consensus with respect to whether these agents require monitoring during pregnancy other than periodic checking of the platelet count. The clinical implication from the available evidence is that LMWHs should now be regarded as the anticoagulant agents of choice for both prophylaxis and treatment of maternal venous thromboembolism.