Anticoagulation in Patients with Mechanical Valves during Pregnancy

Mechanical valve thrombosis is a life-threatening event, while pregnancy is associated with a hypercoagulable state. Thus, in pregnant women with mechanical valves, adequate anticoagulation becomes even more critical. This prospective study was conducted to establish a uniform anticoagulation regimen for these women. A total of 250 pregnancies in 245 women with mechanical heart valves were evaluated. The patients were divided into 2 groups: group 1 (n = 150) took oral warfarin throughout pregnancy and group 2 (n = 100) received subcutaneous heparin in the 1st trimester and oral warfarin for the other trimesters. Both groups received heparin at the time of delivery. There were no coumarin-induced fetal malformations. Minor thromboembolic episodes took place in 5 women in group 1 and 3 in group 2. Valve thrombosis occurred in 1 woman in group 2 and led to 1 maternal death in this series. The incidence of spontaneous abortion was similar between the groups. We conclude that warfarin is safe and convenient to...