Pregnancy outcome in women with prosthetic heart valves

Objective This study was undertaken to evaluate the risks and pregnancy outcome in women with prosthetic heart valves on different anticoagulent regimens. Study design A retrospective chart review of 82 pregnancies in 33 women with mechanical valve prostheses at a tertiary referral center from 1987 to 2002. The main outcome measures were major maternal complications and perinatal outcome. Results The valve replaced was mitral (60.6%), aortic (18.2%), and both (21.2%). Fifty-four pregnancies (65.9%) resulted in live births, 9 (11.0%) had stillbirths (all on warfarin), and 12 (14.6%) had spontaneous and 7 (8.5%) therapeutic abortions (all on warfarin). The rate of spontaneous abortion was highest in women on warfarin throughout pregnancy (P< .01). The live birth rate was higher in women on heparin compared with those on warfarin (P< .01), and in those on heparin/warfarin compared with warfarin alone (P< .01). There were no maternal deaths; however, 3 patients had mitral valve thrombosis (2 on heparin and 1 on warfarin) necessitating surgery in 1 patient and medical thrombolysis in 2 patients. Hemorrhagic complications occurred in 5 patients, 4 of whom required transfusion. Conclusion No single anticoagulant regimen confers complete protection from thromboembolic phenomena in pregnancy. Despite a high maternal morbidity rate, the perinatal outcome is acceptable when pregnancy progresses beyond the first trimester.