Venous thromboembolism (VTE) is an important cause of obstetric morbidity and mortality. Its management during pregnancy is problematic because anticoagulants, the cornerstone of initial therapy for VTE, may have significant foetal as well as maternal side effects. Unfractionated heparin has been the anticoagulant of choice in pregnancy; however, there is growing clinical experience with low-molecular-weight heparin (LMWH) in this patient population. A recently published systematic review of the literature suggests that the use of LMWH during pregnancy is not associated with adverse foetal/infant outcomes. Moreover, its long-term use appears to be safe for the mother, as symptomatic osteoporosis, bleeding and heparin- induced thrombocytopenia occurred only infrequently. There are limited data regarding the efficacy of anticoagulant therapy in the treatment of VTE during pregnancy, and treatment recommendations have largely been extrapolated from data in non-pregnant patients and case series of pregnant patients. This paper will briefly review the challenges and areas of controversy associated with the use of anticoagulants in the treatment of pregnancy-associated VTE.