retrospective study of patients who were treated with fondaparinux pre-, peri- and/or postpartum for prophylaxis or treatment of venous thromboembolism

Conditions: Thromboembolism; Venous Thromboembolism

Summary: the objective of this retrospective study is to gather information about how fondaparinux is used pre-, peri- and/or postpartum for both the prophylaxis and treatment of venous thromboembolism (vte) in order to fill an information gap concerning the off-label use of fondaparinux during pregnancy.

during pregnancy there is a generally enhanced risk to develop venous thromboembolism (vte). although such events are rare they may lead to serious risks for the mothers´ and children´s health. compared with non-pregnant women, pregnant women have an about five-fold risk to develop vte. due to their characteristic spectrum of side effects and the generally long duration of exposure in pregnancy the preferred anticoagulants may produce potentially dangerous side effects, as bleedings, heparin-induced thrombocytopenia (hit), allergic reactions, osteoporosis, or congenital anomalies. today, low-molecular weight heparins (lmwh) are the preferred agents for anticoagulation in pregnancy. compared with unfractioned heparins (ufh) lmwhs have the advantages of a lower bleeding risk, a lower rate of allergic reactions and hit, a more predictable response and a longer half-life that makes dosing more convenient (od or bid). still, there is a considerable proportion of pregnancies where heparin intolerance (allergic reactions or hit) that make it inevitable to change to another anticoagulant. on the one hand, fondaparinux has repeatedly been reported successful in the vte prophylaxis of pregnancies where allergic reactions on heparins, or heparinoids, had occurred. additionally, a considerable amount of oral reports have reached gsk about an additional number of successful cases in the past. on the other hand, we have no systematic and overall view about how many pregnancies have already been treated for which reasons, and how successful they were. due to an increase of certain risk factors, as obesity or the growing age of mothers at childbirth with the associated need for anticoagulation, we expect an increased number of cases where alternative anticoagulation to heparins may be needed. there are a number of potential advantages of fondaparinux over heparins, such as a once daily application, no dose adjustment needed to body weight and no monitoring of thrombocytes, a lower potential for causing intolerance reactions and no risk for hit. the objective of this retrospective study is to gather information about how fondaparinux is used pre-, peri- and/or postpartum for both the prophylaxis and treatment of vte in order to fill an information gap concerning the off-label use of fondaparinux during pregnancy.

Eligibility criteria:
inclusion criteria: * patients who were treated with fondaparinux pre-, peri- and/or postpartum for more than 7 days for vte prophylaxis or treatment, especially those with a history of abortion, and/or stillbirth, vte, severe fetal and maternal complications during pregnancy, severe inherited or acquired thrombophilias, long-term anticoagulation (e. g. patients with mechanical heart valves) and/or intolerance to heparins or heparinoids or heparin-induced thrombocytopenia (hit) exclusion criteria: * patients who were treated with fondaparinux for less than 7 days * patient who were treated with fondaparinux only postpartum

Keywords: prophylaxis venous thromboembolism postpartum fondaparinux pregnancy