To assess the maternal and fetal risks in patients with
cardiac valve prostheses, a series of 223 pregnancies in 156 women was studied. In 68 pregnancies (group I) treatment with
antiplatelet agents was substituted for that with coumarinics from the first trimester on. Group II (128 pregnancies) received coumarinics through the thirty-eighth week of gestation. Three patients in group I died as a result of
thrombosis of their caged-ball valves. The incidence of
cerebral embolism was 25.0% in group I and 2.3% in group II patients, while that of
spontaneous abortion was 10.3% and 28.1%, respectively.
Coumarin embryopathy was found in 7.9% of group II infants.
Fetal death did not occur in the 12 cases in which subcutaneous
heparin was substituted for the
coumarin derivative in the first trimester and the last 2 weeks of pregnancy (group III), but maternal
cerebral embolism developed in 8.3% of the patients. Finally, uneventful pregnancies and deliveries were observed in 12 of 15 mothers (group IV) with
biological prostheses who received no
anticoagulants. It is concluded that (1) women with
cardiac valve prostheses should be counseled against becoming pregnant, (2)
antiplatelet agents do not provide protection against
thromboembolism in these patients, (3) because of the high incidence of
fetal death and
birth defects use of coumarinics is contraindicated in the first trimester and the last weeks of pregnancy, (4) the substitution of
heparin at these times may decrease the incidence of these complications, and (5)
bioprostheses are indicated in women who wish to bear children.