Anticoagulation in Pregnant Women with a Bileaflet Mechanical Cardiac Valve Replacement

BACKGROUND: We investigated the risk and outcome of anticoagulation in pregnant women who had a mechanical valve. MATERIALS AND METHODS: This retrospective study was undertaken for 41 pregnancies (27 women, 33.1 +/- 4.7 years old) from January 1990 to December 2005. Patients were divided into 3 groups: group I (n = 5) took warfarin throughout the pregnancy, group II (n = 18) took heparin throughout the pregnancy, and group III (n = 18) took heparin in the 1st trimester and warfarin from a gestational age of 12 to 20 weeks. RESULTS: Twenty-three pregnancies (56.1%) resulted in live births, 11 (26.8%) in stillbirths, and 8 (19.5%) in spontaneous abortions (SA). In group I, there were 2 live births (40.0%), 2 stillbirths (40.0%), and 1 SA (20.0%); in group II, there were 10 live births (55.6%), 1 stillbirth (5.6%), and 7 SA (38.9%); and in group III, there were 10 live births (55.6%), 8 stillbirths (44.4%), and no SA. No significant difference was observed between the 3 groups in terms of successful delivery rates (P = .826). CONCLUSION: The probability of successful delivery was low. No single reliable anticoagulation protocol in pregnant patients with mechanical valves emerged from the collated data.