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 .
C0040038
thromboembolism
C0019134
heparin