Why do some pregnant women take LMWH?

Why do some pregnant women take LMWH?

Pregnancy induces a state of hypercoagulability but the risk of thromboembolic complications is rare. However, some parturients require anticoagulant medication during the antepartum period, such as those with disorders of hemostasis, mechanical heart prostheses, or at high risk for venous thromboembolism. Additionally, anticoagulant medication is used in women with a history of fetal loss related to thrombophilia and hypercoagulable syndromes, such as antithrombin III deficiency, antiphospholipid syndrome, and protein C or S deficiency. Warfarin causes abnormal fetal development and congenital malformations during the first trimester, such as nasal hypoplasia and skeletal dysplasias. It also increases the risk of maternal and fetal hemorrhage when given during the peripartum period. Heparin and LMWH do not cross the placenta, are not teratogenic, and are unlikely to cause fetal hemorrhage. LMWH has gained widespread use in pregnancy, and has certain advantages over UH. UH and LMWH have similar hemorrhagic complication rates and antithrombotic efficacy.

However, LMWH, unlike UH, does not require laboratory monitoring. Also, there is less risk of serious complications with LMWH, such as heparin-induced thrombocytopenia and osteoporosis.