PREGNANCY IN PATIENTS WITH VALVULAR PROST HESES - RETROSPECTIVE COOPERATIVE STUDY IN FRANCE (155 CASES)

The maternal outcome in the group of 108 mechanical prostheses was com plicated by 16 thromboembolic events (TE) including 10 prosthetic valv e thromboses which required emergency valve replacement in 4 cases, 6 systemic TE in 13 mitral, 2 aortic and 1 pulmonary mechanical prosthes es. The TE were four times more frequent in patients on heparin than i n those on oral anticoagulants. There were 4 deaths, 3 among the 10 pr osthetic valve thromboses (one reoperation, two sudden deaths). Seven of the 74 bioprostheses were reoperated for degeneration on average 5. 9 years after the initial operation but there were no deaths or TE. Th e outcome of pregnancy was 99 children (63 %), 49 of which were born t o mothers with mechanical prostheses (53 %) and 50 to mothers with bio prostheses (80 %) (p < 0.001). Seven of the children were born prematu rely, all mothers being on anticoagulant therapy. The birth weight was over 400 grammes heavier (3 kg versus 2.6 kg) in the bioprosthesis gr oup (p < 0.05). The 20 spontaneous abortions (13 %) were more common i n patients on anticoagulants (17 %) than in those without (2 %) (p < 0 .0.2). Congenital defects due to oral anticoagulants were rare (one ce rtain case). There was one case of phocomelia, an abnormality which ha s never been described in this context. The 36 remaining pregnancies w ere still deaths (N = 5), abortion due to maternal death (N = 4), mate rnal complications (N = 8), therapeutic (N = 9) or voluntary abortions (N = 10) (28 mechanical and 8 bioprostheses). Pregnancy with a valvul ar prosthesis under anticoagulant therapy is dangerous for the mother and risky for the child. The therapeutic indications in women of child bearing age should be born in mind. Conservative percutaneous or surgi cal techniques should be preferred in mitral valve disease. In valve r eplacement, a mechanical prosthesis is the valve of choice in the aort ic position where the risk of thrombosis is low. In mitral valve disea se, mechanical prostheses are proposed in patients with mitral fibrill ation or in women who already have a family, whilst advising against f urther pregnancy. In women without children in sinus rhythm, a biopros thesis should be considered because the risk of thrombosis of mechanic al prostheses was 40 times higher in our series, which must be taken i nto consideration together with the risk of reoperation in the medium term with bioprostheses. Accelerated degenerescence was only observed in a limited number of cases in this series. In women with a mechanica l prosthesis at the start of pregnancy, heparin therapy should be pres cribed for the shortest possible period because there, TE are 4 times more common. Heparin therapy is reduced to the two difficult periods s ituated from the 6th to the 12th week (coumarin-induced embryonopathie s) and during the last two weeks (haemorrhage at childbirth and in the postpartum period). All these propositions are a choice of << the les ser evil >>. There are practically no large, prospective, randomised s eries in the medical literature and pregnancy of women with mechanical prostheses remains a dangerous undertaking during which the risk of T E is ten times greater than the usual risk.